How did the people know that John the Baptist was a prophet?

Question: What reasons gave the people to believe that John The Baptist actually was a prophet and wasn't a hoax? Was it simply the Holy Spirit calling on souls or was there some other kind of proof?
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Answer: I wouldn't overthink this one, LukeoX.
God obviously called John to be a prophet and a forerunner to His Son Jesus, the Christ (Luke 1:17). Consequently, in obedience to God's call John presented himself to the people as a witness, called by God to be a testimony to the Light. Put differently, John was a light to the people, and Jesus was the Light of the world (see John 1:4-9; cf. 8:12). John's little light paved the way for the big Light.
When people believed John's message, they proved the sincerity of their repentance by submitting to his baptism. They then became John's disciples (see Matthew 9:14; 11:2; Mark 2:18; Luke 5:33; 7:18; John 1:35; 3:25; and 4:1). The angel Gabriel told John's father that his yet-to-be-born son would come on the scene "in the spirit and power of Elijah" (Luke 1:17). In other words, John's preaching ministry would bear fruit, just as Elijah's did.
Now, what all was involved in being one of John's disciples is not exactly clear to me, nor does the Bible say too much about that. Unlike Jesus, however, I don't think John was called of God to form a denomination such as--oh, I don't know--Baptists perhaps!?
As the Christ's forerunner, he sort of faded into the background shortly after Jesus came on the scene. After all, John admitted humbly,

"He must increase, but I must decrease" (John 3:30).

Not too terribly long after John made that statement, he was beheaded by King Herod. Interestingly, however, just before he died John told his disciples to ask Jesus,

"'Are you the Expected One, or do we look for someone else?'" (Luke 7:19).

Despite John's greatness in Jesus' eyes ("among those born of women," Jesus said, "there is no one greater than John"), even he struggled with doubts about the identity of his cousin(?), the son of his mom's relative, Mary, whom John's mom called "the mother of my Lord"! (Luke 1:43).
Comment: @vsz: No, I stand by my statement. Luke may have written his Gospel decades after John the Baptizer's body was moldering in the grave, but the information he included in chapter 1 of his Gospel was widely available through word- of-mouth testimony for decades. Remember, Luke may have been a latecomer to the Christian faith, but once he became part of the Jerusalem contingent of believers, he was face to face with eyewitnesses of John the Baptizer's ministry. He was a good listener. Moreover, the Holy Spirit brought to Luke's mind the events God wanted included in Luke's Gospel. Don
Comment: I think you might be misunderstanding me a little. I totally agree with everything you're saying about John and what the Bible declares. I'm looking to understand how people really knew he was a prophet. What I gather from your answer is the people simply believed, and maybe that was all there was. I was just wondering if there was a sign or something given to the people to validate is prophethood besides the one given to John's parents.
Comment: "God obviously called John" - it might be obvious in hindsight, but it was not obvious for the people back then, especially as Luke 1:17 has not been written yet.
Comment: @LukeoX: No, I don't believe a sign was given to the people to confirm John was called by God to be a prophet. True to the prophecy given to Zacharias, however, John would come onto the scene "in the spirit and power of Elijah." In other words, people would see in John a kindred spirit of Elijah. And don't forget the power of Elijah, who is best remembered, perhaps, for his confrontation with the prophets of Baal. Did John, like Elijah, perform miracles? The Scripture doesn't say. I tend to think he did not. His anointed preaching, alone, sufficed to bring conviction to the hearts of people.
Comment: To many people in John's audiences John may have been seen as a kook, a weirdo, a crazy man. To those who took the time to listen to him, however, John's quirkiness and strangeness probably faded into the background once the people realized he spoke with Spirit-anointed power and conviction. One final thought: Results, or fruit, are not the end-all and be-all of a ministry which originates in the call of God on one's life. Some of the OT prophets were probably discouraged by the general unbelief of their audiences. They kept on prophesying, however. Why? Because of God's claim on their lives.
Comment: All of that pretty clears up my question. Thanks @rhetoician!
Comment: @LukeoX: You're welcome, I'm sure. Or as the young people say nowadays, "No problem!" Don
Answer: For all the Prophets and the Law prophesied until John (Matthew 11:13).
Commentary - "... 'until John' means up to and including John ... before the inauguration of the kingdom .... The Prophets and the law prophesied until then and, implicitly, prophesied of the new era ... the kingdom itself ...." (D. A. Carson, commentary on Matthew 11:13, The Expositor's Bible Commentary (Vol. 8), Frank E. Gaebelein - General Editor, p. 268).
But if we say, 'From man,' we are afraid of the crowd, for they all hold that John was a prophet." (Matthew 21:26)
Commentary - "John was the last of a long history of OT prophets that looked forward to the coming of Christ." (ESV Study Bible, p. 1842)
Comment: Welcome to SE-C. Please see the Tour and the Help (below, bottom left) as to the purpose and the functioning of the site.
Answer:
John the Baptist wore 'prophet's garb', which was sackcloth. (This was one indication) (Other OT prophets wore sackcloth as well)
Jesus called John the greatest prophet in the Old Testament, so Jesus Himself called
John one.

Jesus Testifies about John
Luke 7:
…27"This is the one about whom it is written, 'BEHOLD, I SEND MY MESSENGER AHEAD OF YOU, WHO WILL PREPARE YOUR WAY BEFORE YOU.' 28"I say to you, among those born of women there is no one greater than John; yet he who is least in the kingdom of God is greater than he."

Sackcloth was made with animal hair, and it was something that was often worn
while fasting. Prophets, wanting to be close to the Lord, fasted.
Answer: John the Baptist was an Essene ,separated group of Jewish Levite's. Kumron scroll confirms it .During that period Essenes lived away from cities their main job is to be pure to God ,their task to copy the Bible OT .people highly respected them hence they listened to John .
Comment: It would help your answer if you could provide source materials for your assertions (or assumptions).  For example, quote the "Kumran" scroll.
Answer: The people knew John the Baptist was a prophet because it was prophesied that a messenger or prophet would precede the coming of Messiah.  Scripture records that an angel tells Zecharia John's father about this.

And he shall go before him in the spirit and power of Elias, to turn the hearts of the fathers to the children, and the disobedient to the wisdom of the just; to make ready a people prepared for the Lord.
  Luke 1:17

To be in the spirit and power of Elijah (Elias) was to be a prophet as was Elijah.

And they asked him [Jesus], What then? Art thou Elias? And he saith, I am not. Art thou that prophet? And he answered, No.
  John 1:21

Jesus wasn't the forerunner; John was, as Elijah.
In turn this fulfillment in John is of a prophecy that related back to this.

Behold, I will send you Elijah the prophet before the coming of the great and dreadful day of the LORD: And he shall turn the heart of the fathers to the children, and the heart of the children to their fathers, lest I come and smite the earth with a curse.
  Mal 4:5-6

To fully answer the question one would also need to understand the 70 weeks of Daniel and the timeframe of the expected Messiah.  In other words, they knew a prophet like Elijah would come first.  Suffice to say that some understood that Messiah would come by 5 BCE.  This meant that the forerunner (John in the power/spirit of Elijah) would also have to be on the scene.  This then is shown as mentioned above in Luke.
A prophet "foretells" or prophecies the future.  In John's case, his job as a prophet was to tell the people Messiah would and had come.  John was 6 months older than Jesus.

The voice of him that crieth in the wilderness, Prepare ye the way of the LORD, make straight in the desert a highway for our God.
  Isa 40:3

That's a powerful verse.
In addition, another function of a prophet was to annoint the king.  A priest would also do this.  And the trumpet would sound.

And let Zadok the priest and Nathan the prophet anoint him there king over Israel: and blow ye with the trumpet, and say, God save king Solomon.
  1 Ki 1:34

That was the foreshadow of Christ, son of David, being annointed at His baptism "by" John (prophet and priest) and with the voice of God heralding.

And the Holy Ghost descended in a bodily shape like a dove upon him [Jesus], and a voice came from heaven, which said, Thou art my beloved Son; in thee I am well pleased.
  Luk 3:22

So, the people knew John was a prophet.  It was prophesied.  It was required within a certain time.  It was fulfilled.
Answer: There are little of the expected cues and clues to clinch the question asked.
What sparseness there is has been given.
I can only add that there was an unusual yet genuine and ferocious loyalty demonstrated toward John which would confirm Jesus having accorded him- not greatest prophet status- but that of "greatest of men ever born of a woman".
Jesus was able to gain an advantage- knowing the fierce devotion of the Jews to John as the challenged leveled by the scribes, elders and priests to declare the source of His authority- He made them first answer about JOHN'S authority.
They did not answer because "they feared the Jews".  A wrong answer from them there would create more trouble than what they wanted for the answer from Jesus.
Can we glean from this that the Jews considered John the Baptist a prophet?
With that kind of loyalty- I would answer yes.
Answer: Easy! Anyone that foretells of future events is considered a prophet. A true prophet is one that forecasts correctly. A Hebrew prophet from God is anyone that correctly forecasts about events that influence the Jews/Israelis or their nation. Therefore John the Baptist was considered a prophet.
Comment: Could you point to examples of correct forecasts from John? Otherwise I think your answer is incomplete.
Comment: You are using the wrong meaning/sense of the term.  The salient meaning/sense of the word "prophet" is *one who speaks the inconvenient truth.*  The OT prophets were all about that. Their role (for which few were thanked, and many were punished/abused) was to speak God's truth and to encourage / shame people into turning back toward God since they had already turned away from Him .... see also the the origin of the term *repent*


Can I ask about how to use a specific ingredient? (AKA: Culinary Uses Guidelines)

Question: I have an ingredient that I'm not sure what to do with, can I ask how to use it?  Can I ask for recipes including it?
Answer: A question asking how to use a specific ingredient is obviously about cooking, but it may not always be appropriate for a question and answer site.
In particular, when the ingredient in question is something commonly found and there are many possible uses involving it, then it will probably solicit a lot of answers, and questions which have lots of answers are not very useful (see this answer for why that is).
There are also an unlimited number of 'Uses of X' questions about common ingredients.  We have to consider what would happen if we started to allow 'What are some uses for onions?' and 'What are some uses for chicken?'.  Where would it end?  These questions are recipe swap questions in disguise.  And those are not allowed.
When the ingredient in question is rare or unusual then it will probably get fewer answers, which is generally preferable, and which will probably be more informative to people.
This implies that we will have to make a decision about which 'Uses for X' questions should be allowed and which should be considered Off Topic.
There are some guidelines both for asking and answering these sorts of questions.
When asking a question of this sort we should try and restrict the ingredients to:

Things which normally would be considered waste.  Questions about stale bread and apple peel are existing examples of this.
Things which are not usually associated with cooking but are edible.  Questions about hops and lavender are existing examples of this.
Things which are extremely rare in most regions and thus not easy to find recipes for.  This is obviously the most subjective, but we could consider things which are not available in a supermarket as the yardstick.  This is not perfect, and any other suggestions are welcome.  A question about sumac is an existing example of this.  Please do your own homework and try the recipe search engines first.

When answering questions of this form we should consider:

Classes of uses are best. eg:

Used for flavouring cakes is preferable to a cake recipe
Flavour pairings in preference to a specific recipe

Your favourite recipe containing the ingredient is not generally going to be useful

So if you have a question of this form, go through this check list before asking it or it is likely to be closed.
Comment: This seems like a pretty good overview of all the points.  I hope you don't mind me making a few formatting tweaks - thought it would make this a little easier to read.
Comment: Don't mind at all.  It's what I'd want.  Should we make these questions community wiki?
Comment: I don't think they should be CW necessarily. There is no rep gained, and we don't really _need_ users with low rep to edit these.
Comment: @hobodave: FAQs are traditionally Community Wiki, although that may be an artifact of having real rep on MSO.  Most likely, if it's truly a FAQ, it will evolve over time and become CW anyway due to the amount of editing.
Comment: Why do you wish to limit the kinds of questions that can be asked? If you don't want to answer a question on a particular topic, ignore it. If questions don't get answered those people will go elsewhere. But when you say "I don't want anybody to answer a question here about cilantro" well, that just seems like your priorities are misplaced. If I want to ask about the possible uses of flour and hundred people want to tell me their favorite cake or bread recipe are we wasting your harddrive space?
Answer: Additional advice for people who have had a question closed and been referred to these guidelines:
If you are looking for information on how to use a common ingredient, please see the following question:

How does one find recipes given an ingredient rather than the recipe name?
Answer: I would like to point out something which is not explicitely mentioned in this answer, but which has been the way we have used this policy over the past years.
Sam Holder's answer mentions that we don't cover ingredients which are so common that you can easily find recipes for them. We define this as being common somewhere in the world, as opposed to "in your country". So, examples like cornel cherries or whelks would fall under the "so common that they should be closed" policy even though I suspect most users of this site don't know that they exist, much less than they are edible.
This may strike you as unfair or defeating the point, but the alternatives are worse. First, we could define it as "so uncommon that the asker has never heard of them". This means that we have to accept questions on a lot of stuff which is a staple in our kitchens but not present somewhere else, bringing us back to square one with all the big list questions we are trying to avoid with this policy. We could alternatively define it as "uncommon in the US", which would cover the experience of the majority of our users, but that would be opposed to our policy of doing our best to be more international and make users from all countries feel welcome, so I'd rather not go there.
This leaves us with the policy of closing questions which many people here would consider interesting and would be sad to see go. I agree that this feels unpleasant on the first glance, but consider that we don't have to be everything for everybody. If a search of "X uses" or "X recipes" or "how to eat X" brings you enough search results, there is no need to rehash them on our own just because it is novel to us.
Comment: And very roughly, our standard for "common somewhere in the world" is in practice mostly just going to be whether you can easily use Google to find recipes (in English - don't worry, we're not expecting people to learn Chinese to go search for a specific ingredient).


Holonomic robots using Mindstorms

Question: I just got some Rotacaster wheels and want to try building a 3 wheeled Mindstorms omnibot (holonomic robot) and I'm looking for a practical (easy) discussion about writing a driving program.  I've found some theoretical papers but need something a little easier to implement.  Has anyone here built one and what advice can you give?
Answer: I got also the wheels and found it really interesting... so I wrote an article were I explain all the maths and show you how to build one yourself ( instruction attached ) http://thetechnicgear.com/2014/04/howto-build-3-wheels-holonomic-robot-using-lego/

The code is for EV3 software and I will surely rewrite it for leJOS ( despite there is a class that already does the work ) on the following weeks.
Answer: There is an excellent model at Hitechnic, complete with building instructions and example programs. It's for NXT, but shouldn't be very hard to adapt to EV3.
Answer: Here is an article that may be useful:
http://botbench.com/blog/2014/05/11/omniwheel-article-in-dt-practice/

Holonomic robots using Mindstorms


Are microsatellites viable markers for GWAS?

Question: I'm just reading some papers on genome-wide association studies and find that most of them use SNPs as a marker. I understand that they're the most polymorphic and thus the best for accurate correlations, but would microsatellites provide another viable method to check for genetic correlation?
They're highly polymorphic and small enough to showcase differences, while maybe allowing for more statistical significance.
Answer: Microsatellites could be used for GWAS. Actually they were the basis for linkage studies and were also used in the first association studies. The main reason why they have been replaced by SNPs is that in the human (or other organims') genome, there are by far more SNPs than microsatellites.
GWAS rely on linkage disequilibrium between the marker and the real causal variant. LD decreases quite fast with distance, thus, the more markers you use, the more likely you are to genotype a marker in LD with the causal variant. In the end, I would strongly recommend to use SNPs to perform GWAS.


How to get rid of ants

Question: Recently my house has had an ant problem. I'm plugged up the holes I think they're coming in from but I still see them wandering around the house and getting into my food.
How do I get rid of them without professional help?
Comment: Related: http://lifehacks.stackexchange.com/questions/3940/pest-control-natural-method-of-ant-control-howto
Answer: I have always used ant poison like nipon which the ants will take back to the nest and it will kill the queen. This is not a fast solution but given time works well.
Comment: Not really  a hack but a good answer
Comment: "nipon" which poison is this? is this a commercial brand?
Answer: This really really depends what type of ant.
Most you can just keep spraying til they give up, die off or decide somewhere else is more profitable.
Destroying their pheromone paths will prevent hungry returnees. Killing them in your house will prevent them returning to the nest to set a pheromone path to your comestibles.
Things which are smelly &/or sticky make good path-breakers. Vaseline they will not cross even though they can still smell the other side of the path. Hairspray works for a day, then loses its potency. Lighter fluid washes the path away, but doesn't prevent their return & is also a bit flammable ;)
Pharoah ants, on the other hand, can only be killed by feeding them with a hormone which prevents their breeding. If you try to kill/spray/squish pharaohs, they go into 'under attack' mode & all turn into breeding females & dissipate - not what you want - you will end up with tiny nest sites everywhere.
[This, strangely is not borne out by the wikipedia link - but was what I was told by the exterminator who came to rescue us from an invasion we were unable to deal with ourselves after 6 months of poisoning & the methods described above, which have been pretty successful on every other ant-type. It may have just been a poor or misinterpreted version of the 'budding' which that page does discuss - nevertheless, pharaohs need specific pharaoh 'poison'.]
Comment: For path-breaking, you can also try paprika - pour a thick line along the place where the ants enter. (I live in Spain and so it's easy to get, but I imagine you can probably find it in a supermarket. Get the spicy kind, since off-brand paprika is usually a bit feeble.)
Answer: I had a problem with ants for a while, and you can do one of two things.

Put baking soda near doors or anywhere you think the ants might be getting in.
Poison the anthill.
Answer: Mix powdered sugar and Borax, pour it wherever you see them. They will take the stuff back to the nest. Even ants deserve a last meal!
Answer: Petroleum Jelly. Apparently, ants cannot cross it or tunnel through it. Try spreading a line of Vaseline in the corners of your cupboards, and use it to plug those holes.
Answer: Terro is the most effective we have found, but the key is to follow their directions.
Place it in your house where the ants are, and in a couple of days or so, no more ants!
We have used it for several years.
Answer: I've used TERRO Liquid Ant Killer to successfully kill ant hills.  Not in accordance with the instructions, I tore up the visible anthill, waited for ants to start appearing, then poured the product directly on them and covering most of the major holes.
I've also read about mixtures of honey and borax, and lots of other solutions on Google.
 From what I understand, most of the store-bought liquid ant killers are simply a mixture of borax and something sugary.
I've also heard that powdered cinnamon will coat the ants and either break down the joints or exoskeleton, causing them to die, or it hardens on them like cement.
If you want some art work and have access to a decent furnace, pour liquid aluminum down the ant hill.  The aluminum goes quite a ways into the hill before solidifying.  Digging up the cooled aluminum makes for a very interesting sculpture.  Look it up on YouTube for some of the amazing structures people have gotten from doing this.
More (or less) on heat, you can supposedly pour boiling water into the anthill to kill everything.  It'll take a large pot of water, but it's more environmentally friendly than most of the other options you'll find.
Wiping down surfaces with white vinegar will help remove their trails.  Supposedly they hate the smell of vinegar.  I put an open bottle of vinegar under my kitchen sink, which was an entry point for the ants, and got rid of them from my apartment fairly quickly.  The bottle only had a few ounces in it, so it eventually evaporated, but I didn't notice any vinegar smell while it was fresh.  Of course, my landlord was also spraying for ants, so vinegar wasn't the only factor here.

How to get rid of ants


Why mount multiple autocannons on a fighter or CAS aircraft as opposed to a revolving barrel auto-cannon with a higher rate of fire?

Question: Why would one design an aircraft with multiple chain guns instead of a single large rotary cannon, like the GAU-8 Avenger, and similar weapons?
Comment: ehum, what's "mini" about the GAU-8?
Comment: Who does that? I mean, do you consider two to be "multiple" already?
Answer: Image source
Same difference as between a shotgun and a rifle: if you need to hit a moving target, like a clay trap target or pigeon or aircraft, it's best to spread the projectiles out so that there is more of a chance that the target meets them. If however the target is (almost) stationary, nothing beats lining up carefully and inflicting the maximum damage with the projectile.
Heavy machine guns are mounted on swivels to create an effective area instead of a line, and only one bullet would be required to stop a soldier. A trap shooter swivels while overtaking the spinning disk, thereby spreading out the spray of shot. But an A-10 lining up for a tank kill wants to maximise impact upon this one tank only - just the one bullet landing anywhere on an armoured tank may not do the job.
When multiple cannons/machine guns are mounted across the wings, the aircraft is set up for dogfighting. Which they are not designed for anymore.
Answer: Possible reasons are:

Spin-up time of the barrels of a Gatling-type cannon is larger than for a typical chain gun. The effective rate of fire for short bursts with the chain gun is higher than for the Gatling type.
Higher rate of fire with multiple chain guns than with the Gatling-type gun (from slightly higher to much higher), assuming same number of barrels.
Weight: the weight of a Gatling-type gun is usually higher than for a single(!) chain gun. There is a trade-off with rate of fire, depending on the Gatling and chain gun variants.
Comment: Don't forget redundancy. Also I remember reading that some fighter pilots liked their guns aimed at a single point, while others like them aimed at slightly different points. This couldn't be accomplished with a single gun.
Answer: A gatling type gun takes a certain period of time to reach it's designed rate of fire. The M61 20mm gun takes about 0.5 second to reach 6000 rounds per minute, which means that during the first half second only about 25 rounds are fired, whereas a battery of four revolver cannon each firing at 1200 RPM would fire 40 rounds in the first 0.5 second.
Answer: One reason could be :
Frontal surface of disk plate holding and spacing each canon is greater than the frontal surface of independent canons.
More frontal surface provides more drag.
Comment: I'd say it's probably the volume of the gun behind the front that's a bigger impact.  Having multiple small receivers and ammo magazines give more flexibility in packaging/installation.  With the GAU-8, the A-10 was literally designed around the gun. If you're starting with an existing airframe design, something like the GAU-8 is not really an option.
Comment: @Gerry Your right & that's why I said "one reason" I was assuming the volume of the gun behind was inside the airframe, without modifying its aerodynamics. Anyway guns in planes are like snow rackets on asphalt roads.
Answer: The only advantage would be redundancy.  If one gun jams, you still have others which can fire.  The primariy disadvantage to a multi gun scheme is weight.   A single gun has one action, receiver, magazine,  and ammunition feed system, where is multiple guns will each require those components for each of them.   Multiple barrels on a single gun solves the problem of a rapid fire action while providing cooling of the barrels during operation.  Multiple guns also consume more space inside of the aircraft, which limits additional real estate for things like fuel, mission systems etc.
Additionally,  you're not really using the right terms there. Miniguns were a trademark of General Electric, which developed a scaled down version of their rotary cannons chambered for the 7.62 x 51mm rifle cartridge for use on gunships.  GE also manufactured a variety of rotary cannons of varying calibers for use on aircraft, including the M-61A1, GAU-8/A, and others.
Comment: Did you read the question?
Answer: On a fighter, you'd mount multiple guns if the high speed rotary gun hadn't been invented yet, which was the case in WW2.
The rotary gun is lighter that multiple guns, takes up less space, has a higher rate of fire, and is more accurate than multiple guns firing at a slower rate.
WW2 guns were typically wing mounted, and all guns set to converge at a fixed point, typically around 200 yards. If the fighter pilot shot at a plane not at that point, a good deal of the bullets would miss.
Even with the few planes that had centrally mounted guns like the P38 and ME110, the recoil of the individual guns would cause their aim to diverge, though it wasn't as pronounced as wing mounted guns. Some F86 pilots in Korea added reinforcements to the mounts for their six Browning M2's in the nose, to keep them from moving so much while firing and improving their accuracy.
The single high speed gun puts all the bullets in the same place, regardless of distance. Given the difficulty in getting another aircraft in one's sights, the ability to inflict a much higher level of damage in a short period of time is a real advantage.
For CAS, especially helicopters, slower rates of fire stretch out the ammunition supply, for softer targets that don't require a huge amount of damage in a short period of time. After all, a soldier is just as dead whether they get hit by two bullets, or two hundred. Note that this is for dedicated CAS helicopters that are expected to loiter near the combat area for long periods of time.
When the potential target becomes hardened, like a tank, then the GAU8 at it's full speed does what the CAS pilot wants: puts the maximum destruction in one spot, in the minimum time.
Some helicopters, such as the MH53, come with a single 7.62 rotary gun in the back, but it's job is not continued CAS, but suppression when inserting or removing troops from a hot LZ, which is done as quickly as possible, and then the helicopter departs the combat zone. A stream of bullets from a rotary cannon tends to make soldiers seek cover, and stop firing at you.
One other CAS aircraft that uses rotary guns is the AC130. It is expected to loiter for long periods of time, but the AC130 can carry a lot of ammunition, so running out isn't as much of a concern as it is with a load limited helicopter.
Gun choice for ground troop support depends upon the expected mission.
Comment: BF 109, FW 190,  P61 black widow, P39, Mosquito, Beaufighter. Nose mounted guns during WW2 are not nearly as rare as you made out. The spread caused by having wing mounted guns is often considered an advantage. Pilots more likely to hit with a shotgun than a sniper rifle. For an expert the sniper rifle is better but for average joe with <20hrs going into combat the shotgun approach is going to be better


Can I share my Android's VPN connection over a Hotspot?

Question: I recently purchased a Chromebook which doesn't support my companies PPTP VPN. As a workaround, would it be possible to connect to the VPN on my Android (4.4) and share that connection over a hotspot? If so, how?
Answer: Unfortunately the stock Android tethering application does not work with VPNs. This limitation is an oversight in the software and not a system limitation.
However there is an application called ClockworkMod Tether that will allow you to tether and use a VPN at the same time. In fact it makes use of the standard tethering application and then fixes up the routing information to make it work.
This application does not require you to root your phone but you do need to run software on the computer that you wish to connect to your phone. Also this only works for USB tethering at the moment.
There are other alternatives to ClockworkMod Tether, if you wish to try them, including PDANet.
Hope it could help
Comment: This worked for me using PDANet. ClockworkMod seemed to want permission to use everything. PDANet needed a lot fewer permissions, but I'm still not 100% certain of its safety.
Answer: I found some information that consists of adding iptables rules using command-line in your rooted device.
I tested it on my Android 4.4 on Blu studio and it works fine.
Quoted text originally written by  SmokeyTech1 of XDA-Developers here:

You need a rooted device
Make sure you have a VPN app, like OpenVPN or DroidVPN ( I use DroidVPN and its the best)
Download Terminal Emulator
Activate your hotspot and connect to your VPN
Launch Terminal emulator and on the first line type "su" (without the quotes) and press enter
Copy and paste this to the Terminal Emulator. Make sure to paste to a new folder using Root Browser first and copy to T.E. in the exact format as shown below:

iptables -t filter -F FORWARD
iptables -t nat -F POSTROUTING
iptables -t filter -I FORWARD -j ACCEPT
iptables -t nat -I POSTROUTING -j MASQUERADE
ip rule add from 192.168.43.0/24 lookup 61
ip route add default dev tun0 scope link table 61
ip route add 192.168.43.0/24 dev wlan0 scope link table 61
ip route add broadcast 255.255.255.255 dev wlan0 scope link table 61
That's about it. Also, be sure to make a folder with Root Browser and paste the code there, as this resets after re-boot. It worked on my LG G3 on android 4.4.2

(Note: Quoted text has been edited to fit the site's formatting style.)
ATTENTION: Part of the rules where it says wlan0, this is interface that corresponds to where you want send the connection.
To send it to the WiFi hotspot, replace it with ap0
The tun0 is the VPN tunnel that you receive from the remote server.
You can list all the interfaces typing netcfg the root terminal

As for terminal emulator, I use ConnectBot:

ConnectBot allows a terminal emulator on your device for connections
  ssh, telnet and localhost.
Comment: Interesting, but a bit tedious to do regularly.  Unless someone has a way to bundle that script up and run it from a home screen shortcut or something similar?
Comment: It seems like this is a perfect opportunity for someone to make a simple app to automate this on Android.
Answer: Yes. F-Secure Freedome (a VPN client) is running on my Note 2. I have Note 2 tethered to an Ubuntu machine and an Android tablet. My tablet and laptop post a Germany IP address, while I am on the other side of the ocean.

Make sure that your data plan allows tethering.
Make sure that you are on the cell network. However, USB tether to Wifi VPN on the phone
works a bit better. I keep my connection dropped when going all over
over the air.
Depending on your flavor of Android your mileage may vary

Note 2 and the tablet are running 4.4 (CM 11 nightlies), Ubuntu is on 14.04.
Comment: Okay, thanks. I will have to play with it some more. I gave it a quick try but wasn't able to access any thing on the private network.
Comment: I've had some issues with it when it was:
 Laptop - wifi - phone - vpn - verizon - internet

However, it worked better when it was:
 Laptop - usb cable - phone - vpn - verizon (or wifi) - internet
Comment: I currently have a Freedome VPN subscription, and using the VPN through USB Tethering isn't working on my end (LGE Nexus 4, Windows 7 PC). If I disable the VPN I'm able to access the unprotected connection over USB tethering.
Answer:
On Android device, install:

Proxoid (run on port 8081).
Internet Sharer (HTTP: 8080, SOCKS: 1080).
Ping & DNS (I need IP address of mobile phone)

Tether Chromebook and phone by USB cable.
Run:

Mobile internet connection
VPN client
Proxoid
Internet Sharer

Set mobile to tether USB connection (check the icon of USB connection on mobile changed).
Find phone IP address (Ping & DNS, Network Info, IP: xxx.xxx.xxx.xxx, internet connection must be active)
On Chromebook, log in, check internet connection, WiFi should be automatically replaced by USB Ethernet.
Click the ethernet icon, Settings, proxy TAB.
Finally set on Chromebook (HTTP proxy host: IP in form xxx.xxx.xxx.xxx, port 8080, HTTPS proxy host IP, port 8081, SOCKS proxy IP, port 1080).
Try to run Chrome and browse intranet (as in mobile).
Answer: This is an extension to the answer provided by João José that would allow you to selectively direct certain traffic to VPN while letting other go directly.
I wouldn't have figured it out without João José's brilliant answer so if you will upvote this, please upvote his answer as well.
# Following rules will allow me to redirect traffic through my vpn
iptables -t filter -F FORWARD
iptables -t nat -F POSTROUTING
iptables -t filter -I FORWARD -j ACCEPT
iptables -t nat -I POSTROUTING -j MASQUERADE

ip route add 192.168.43.0/24 dev wlan0 scope link table 61
ip rule add fwmark 0x61 table 61
ip rule add iif tun0 table 61

# Configure traffic that I want to make it go through VPN
# 1. My DNS
iptables -t mangle -A PREROUTING -p tcp -d 126.96.36.199/32 -j MARK --set-xmark 0x61
iptables -t mangle -A PREROUTING -p tcp -d 188.8.131.52/32 -j MARK --set-xmark 0x61
iptables -t mangle -A PREROUTING -p udp -d 184.108.40.206/32 -j MARK --set-xmark 0x61
iptables -t mangle -A PREROUTING -p udp -d 188.8.131.52/32 -j MARK --set-xmark 0x61
# 2. Insecure websites
iptables -t mangle -A PREROUTING -p tcp --dport 80 -j MARK --set-xmark 0x61

Comment: Not sure what happened, but it worked for half a second. It worked, then I restarted my phone and it didn't work no more :( I'm on android 9.


Why can I see multiple desktops on my laptop display?

Question: I've just installed Ubuntu 12.04 (dual-boot with Windows 7) and the image below shows the current display (6 multiple screens).

Anyone know how to rectify this?
Step-by-step instruction is highly appreciated, I'm a newbie!
Thanks in advance!
Answer: Have you installed drivers for your display? Driver software would probably work. To install them, you will need to access the laptop manufacturer's website. Through the manufacturer's website, you will be able to locate driver software, then download the correct drivers for Linux. Ubuntu will most-likely not be an option.


How can I get answers fast?

Question: How do I ask a question so that it can get a quick response? I see some of the questions are very old and still not answered, but some others get a very quick response.
Return to FAQ index
Answer: The following are some factors that can influence the type of response you get and how fast you get the right response to your question:

Ask a clear, meaningful and answerable question.

Put extra effort in the title; make it specific, concisely capturing the main objective, knowledge gap to be filled, support needed or bug identified, etc.

Tag your question right, and with the primary tag grouping in the SE platform. For instance: #bug, #support, discussion, #feature-request, if on Meta. Often,the system automatically prepends relevant tag suggestions you may choose from.

Keep refining/editing your question until it becomes perfect, even as mentors offer their suggestions.

Be lucky that the expert in your field sees your question.
Comment: Good points. As for the expert, also "be patient": An expert (*The Expert*, even) may well be in a different TZ, and you may get a *great* answer in a few hours (Real Story™).
Comment: Yeah, I get answers pretty darn fast.  Make sure to be explicit with what you want.  Not merely ask for a solution. Like instead of asking, "how much flour should I use for a cake?" ask "I am making a southern velvet cake for six people. How much cheesecake topping should I get for two cakes?"
Comment: Good start but i think there are lots of gaps. Posted an answer below I think it fills a lot of them in :)
Comment: you can also award a bounty to your question i guess
Comment: *"Put extra effort in the title; make it specific, concisely capturing the main objective"* True. But when you have a specific not-so-easy problem on Stack Overflow, you'd get less views, which typically results in less responses...
Answer: Provide enough information. Peter has added a lot of other points, all of which I agree with, but it's usually the lack of information which stymies us.

If "something goes wrong" tell us what. If it's an exception, post the full stack trace. If it's a compile-time error, post the exact error message. (Not "something like this" but cut and paste.)
Don't post code which is "something like" your code which fails - post actual failing code which we can compile and run wherever possible. (See my "short but complete" article.) It's very frustrating to point out errors only to be told, "Yeah, but that's just a typo - it's not in the real code."
Read your question to yourself after typing it out, trying to imagine that you're coming to it with no other information. Does it still make sense? If you were trying to answer it, is there anything else you'd want to know?

Oh, and respect people who are trying to help you. If you become argumentative with answerers, they'll just go elsewhere.
Comment: +1 for the respect thing
Answer: All the other answers are right, but people will not try to help you if you haven't gotten your "hands dirty" with the problem. You'll notice that the process of specifying the question pushes you further in the debugging and testing of what you think is happening. Keep going! Many times you resolve the question yourself, or it derives in something that you really don't know that is actually useful to everyone.
Bracketing: Try to get the problem to be as small as possible. You might think that you're asking about 50 lines of code, but if you can figure the one line that is not working, people can easily help you. Few people want to help you figure out which of your 50 lines of code is not working. Also, if your question is a dupe or easily answered on Google, you should know it before they do.
Find all dupes, and find an SO answerer that is the right person to ask the question: To do this you will have to find all SO dupes of your question, and you might find that it's answered already. But if you find something really similar but different, comment the best answer response and ask politely if they might care to look at your question.
Answer: If somebody then asks you a question (usually in the comments on your post), answer them. They are generally asking for a reason, and can't give a clear reply until you have clarified something.
Answer: Twitter the title of the question (and url). There will probably be someone with a keyword search who will notice your question and head over to help you out.
Answer: Write your title clearly so people will look at it, and explain your problem well so they don't leave in confusion.
Tag specifically and appropriately, so those who know the topics will look at your questions.
Answer: Another factor is the size of the community you are talking to. Questions with popular tags get more answers more quickly than questions with less popular tags.
Of course, I am not trying to say that you should tag your questions with ill-fitting tags.
Comment: I am tagging this answer 'sex' and 'boobs'
Answer: In addition to the other answers given here, I would also add that for really fast and good responses, ask at a time of day when many software developers are using SO, so usually working hours would be good.
I suspect about 2pm - 5pm (GMT) would be good because you get the bulk of European software developers at work and the bulk of US-based software developers at work.
Comment: I disagree. You will get more and faster responses at peak times, but the better quality responses come on weekends. I have no data to back this up, of course.
Answer: All the steps below will make your question get an answer quicker. Some points apply only to stackoverflow but their core message is good to keep in mind for all SE sites.
Short answer:

good title
Make question easy to read make it short
Format code correctly. Indent etc. (look below for more detail!)
Provide background
Make your question most generic version of a specific problem
Provide code that actually stands on its own
Edit your question often
Use correct tags on your question
Post links to your question elsewhere
Clarify all the questions other people have about your question
Show that you have worked on the problem yourself

Full answer with explanations

Make sure you have a good title
Make sure that you make your question easy to read -means short! Post most important information first, if its a programming question post only a snippet of your code first and if you need to provide more details post more of your code below (its even better to post a snippet in the question and provide larger pieces as an external link it makes it more likely that people will not just click on your question see that its long and run away)
Make sure to format your code correctly.  Your code should also be presented in the most generic way. If you are doing tons of other things that are not related to the example cut them out of the example (its good idea to actually cut them out and then run your code again to see if the problem actually lays where you think it does and then post that example) Its important if you do this to post your actual code as well (possibly as an external link) if you dont you might get a quick answer but not a one that answers your actual question with your full code which might frustrate both you and the person that just answered  Indent your code correctly, and use names that are easy to understand for everybody thats not involved in your project. (it might seem like a good idea to name your variables sz_vamps_cong_toogle but if you are posting a small snipplet that has no other toogles it's best to just name it toogle keep it minimalistic, again if you do this you need to provide your actual code)
You can also provide external links for other material that is just too long for a question. Following this step might prevent you from getting the right answer if you dont simplify your code correctly so if you arent sure just dont do it
So use this with caution and try to avoid falling into the xy problem trap
Provide a lead in or a background. Ask the question in the way that everybody can understand what you are asking for before they even look at your code.
Make your question is most generic version of a specific problem (so don't ask how do i make my input fields disappear in this code - ask how to fade an element out/in in jquery it will help other people in the future as well)
Provide code that actually stands on its own (or for other sites provide a question that stands on its own without having to look for too much outside information). In some cases this means providing a code that once copy pasted will compile/work. Its also good idea to provide a link to a working example if possible (like a link to jfiddle if its jquery related) Its best to post links to information that might be needed but takes up a lot of space.
Edit your question often - first of all it will improve the question but it will also make it go up the list so people can see it.  (and shows that you are still interested in the question so more likely to check the answer and accept it as best. If you are not satisfied with the answer you marked as best you can edit your question and see if anyone else posts a better answer, turns out there is already a question about that)
Use correct tags on your question. Don't put just one tag put as many as you can think of if they are appropriate, if you have too many discard ones that are not as popular. People that search for questions by tags will be able to find your question easier and it will get more attention and will get answered quicker. You should not put tags in titles (even if it can bring you a faster answer)
Post link to your question on forums on other website, send them to your friends and people that are interested in the topic. Even if they don't know the answer question with more views are overall more likely to be answered and some of the other people you share your question with might also share it with others. (Please dont spam people it might work but I hate to be the one responsible for such an idea)
Clarify all the questions other people have about your question. If people are confused about something they will not be able to help you with your question and they might not be the only ones that are confused but the only ones that are speaking up.
Show that you have worked on the problem yourself and provide what you came up with. People will be more willing to help you if you show that you tried to find a solution and you are not here because you are too lazy to do any work yourself.

How can I get answers fast?


Ways of nudging a misplaced sub-question into its own post?

Question: Example: User "Samir Patel"'s first question as a new user today. Deleted as it should have been since it was attached as an answer to another question, however it would have made a very answerable question if published as one. Since it is not commentable, and there is no private messaging (thankfully, most of the time), how to help such questions find their own spot, instead of it all ending with a newbie leaving frustrated? Reformatting and reposting the question as me would be clearly robbing the original poster. Commenting the main question would be out of place too AND be very confusing to non-moderator-tools users.
Answer: There's absolutely nothing wrong with reposting, if you feel you understand the question well enough to make it clear. It's not great if people are likely to need to ask for further details and clarification, since you may not actually know how to respond. This is definitely not "robbing". If you put in the time to write a clear question, and post it as a question, you deserve the handful of upvotes and the reputation that comes with them.
The answer you mention... well, it looks a wee bit broad and vague, so I wouldn't want to adopt it myself, but if you think you can, go for it.
We mods do generally comment before deleting, though sometimes we don't have time, or figure it's not worth it if the answer is very far from a reasonable post. (I wasn't the one who deleted that specific answer, so I can't speak to why it doesn't have a comment.) Note that anyone can comment, e.g. when flagging for our attention, so you don't have to entirely rely on us. That said, honestly, it's very rare that a user actually heeds the comment and posts their question as a question.
Beyond adopting a question, or commenting on the answer before it's deleted, there's not really much else we can do within the framework of the site.


Visual Studio 2008 - Microsoft Document Explorer - very small font

Question: When working with Visual Studio 2008, When I open any help page in Microsoft Document Explorer, the font is so small I can't read it. Under Tools: Options: Environment: Fonts and Colors: Show settings for: I have only 'Environment Font' option (this option changes the font of the application, but doesn't change the font of the displayed webpage).
When I right mouse click on the webpage: Text Size: this is already set to 'Largest'.
Repairing Microsoft Document Explorer from Add and Remove programs didn't help.
How can I fix the font in Microsoft Document Explorer?
Answer: Follow the instructions under this link:


How do I use my PC as a Public Address system

Question: I have a set of external speakers for my pc which work very well. I have a microphone which works very well with my pc. How do I get the sound that I make into the microphone to come out the speakers and thus use my pc as a public address system for when I am giving talks in places that there is no PA system?
Answer: By running an Icecast server we are able to stream audio to either a local network or to the internet (see also project home page).
When running Darkice we can also stream any audio output of our local sound card live as an mp3 stream (with a minimum of 1s delay). The receiver side is OS independent but needs to be able to connect to an internet radio stream created by Icecast. Most audio players are capable to do so.


Combine all the comments add up to an answer?

Question: thick, crunchy, fluffy corn flakes breading I'd like to consolidate the comments into one answer, but only a couple of the comments are mine. Would it be appropriate to use the wiki option for this?
Answer: Community Wiki is for answers that you want or expect to have improved, edited, or generally maintained by the entire community, freely and without restriction - including users who just registered and have no reputation on the site - for better or for worse.
It's not a recommended or particularly useful way of announcing that different pieces of an answer came from other people. That's normal for any answer, if you think about it. If you're asserting that the answer is a reasonably complete answer and isn't an ongoing effort by the community (i.e. like a Wikipedia page) then it's your answer, not a community wiki.
Comment: @Jefromi Excellent point. In this case someone else beat me to it (which of course is fine), but you're absolutely right. This issue has come up more than once. *If you can answer the question, answer it!*
Comment: Agreed, and if you want to feel good about it too, just note that none of those other people wrote an answer, they just wrote comments, while you're providing the thing we really want.


Do I need to do a title search on land? how about title insurance? lawyers?

Question: I am looking at a piece of land that is being sold for 25k. As I understand it, I need to do a title search before any transaction is done. I've already looked at the tax assessors website and seen that the taxes appear to be up to date and that the information about the owner seems to be in order. Do I still need to do a title search?  If so can someone recommend a good place to get a title search performed? I'm also looking for some advice on title insurance and lawyers. As I understand it, title insurance is something that is procured at closing. As for lawyers, so I really need a lawyer for a transaction of this scale? or is that overkill. I'm jus trying to get a handle on what is required and what is optional.
Comment: This question (still) needs a country tag
Comment: You might have better luck on http://law.stackexchange.com/
Comment: How long is a title search good for.... Certain amount of business days before it expires and we would need another completed?
Answer: Title search: Start by walking into the town offices and asking to see their records for that plot. This will show who owned it when,  often how much it was purchased for, and should include most restrictive covenants or rights of way that could limit how the property can be used. (Building codes and zoning will of course impose other restrictions.) That won't necessarily prove that every possible defect in the title was addressed, but if the records are continuous back to or past the date of constriction you are probably fine. A more professional search will probably be done by your lender.
Title insurance: Ask your lawyer if it's worthwhile given the laws in your area. Remember that it's so cheap because they rarely need to pay out significant amounts.
Remember to ask the seller whether the title insurance they purchased (if any) is transferrable. If so, you almost certainly don't need to purchase more.
Finally: This is going to be one of the smallest numbers at the closing. If you do buy it unnecessarily, the resulting "confusion tax" is not the end of the world.
Answer: You do not need a lawyer, you don't need a title search, and you don't need a lawyer; if you don't have a loan. All the risk is being borne by you. If there is an issue with past ownership, or a misunderstanding on the easement, or that the sales contract didn't convey everything you thought, or that the post sales paperwork wasn't filed correctly; any loss will be limited to your time, energy, and money.
Of course if there is a loan the lender will insist on protecting their investment. They may require a title search, title insurance, and they may ask to review the contract. They will also be happy to know that all the proper paperwork is filed correctly.
If the purpose of the land is for your personal use you might never need to get lawyers and insurance involved. But if the purpose of the purchase is to build a structure you might need to get them involved in the future. Even if you don't need a loan for that future construction do you want to risk all that money on a paperwork snafu?


How to remotely detect another machine's utorrent version with nmap?

Question: How can I use nmap to find out the utorrent version installed on a PC by scanning it from another PC on the same subnet?
Answer: Looking at the nmap-service-probes database, it looks like nmap can't detect which version of uTorrent is running.
Answer: uTorrent is able to randomise port, so using nmap to detect uTorrent can take long since you have to scan all tcp ports.
Regardless of this fact, nmap tells me :
tcp open  ssl/http uTtermiorrent utserver web interface
If I scan my uTorrent port using -sV option (version detection). It returns nothings.
If you connect using netcat (nc, ncat, socat), there is nothing being returned either when probing for the protocol. (beside a "invalid request")
So unless you manage to find a fingerprint (a output on a connection to utorrent port), you are not gonna figure which version of uTorrent is being used.
I think this is not feasible using network probes :-?


Why disguise as scout?

Question: I've seen quite a few videos on Youtube where spies repeatedly switch to a scout disguise after each kill. Slow scouts seem like obvious spies. Why not choose a Pyro, Engineer, Medic, or Sniper?
Answer: Sometimes using an obvious disguise has its advantages. One example is if you are using the dead ringer. Being obvious can trick people into attacking you and activating your cloak. The enemy might think he just killed a crappy spy and then POW backstab!
Comment: Disguising as FRIENDLY-scout has even more advantages compared to enemy-scout disguise when using Dead-Ringer.
Answer: One reason is that scouts are often seen running around lots of different places on the map, unlike say the engineer, who can normally be found near his buildings. So if you're a spy disguised as a scout, your mere presence in a certain area isn't as likely to arouse suspicion as if you were a different class.
Answer: As well as the other two points (Dead Ringer to get shot and Scouts are generally all over the map), I have my Spy-disguise menu set to short-hand notation, meaning instead of getting a list of classes with the numbers 0-9 to choose them, I get two groups of 1-3, the first chooses either the Attacking, Defending and Special class group, the second allows me to choose a disguise from that group.
So, when disguising quickly, I've found it easier to just hit 4-1-1, which is

4 - Bring up disguise screen
1 - for 'Attack' Group
1 - choose Scout

Which is where my fingers tend to sit naturally on the number keys. Sometimes if I'm thinking about it in advance, I'll choose 4-3-3 (Spy). When I'm actually trying to blend in successfully I'll choose more carefully.
Answer: In my experience, its very good for snipers that see you from a distance. The Scout is hunched over, making headshots hit the Spy's chest instead of his head. As long as the Sniper isn't charged, you should survive. Jumping around does help as well.
Answer: Jump around, strafe, and backpedal. combine this with a low to medium health scout disguise, call medic and help. this is very convincing.
Answer: The only reason why I choose the Scout disguise is that your speed increases/decreases with different disguises (ex. Heavy makes you run slower and Scout makes you run a bit faster than normal). I disguise as the Scout on long maps (such as pl_badwater) so I can get to the enemy faster. Plus, as said before by Colin D, you can trick the enemy into thinking you're a very crappy Spy. With the Dead Ringer (An Invis Watch that can fake your death), you can fake your death, sneak behind the enemy that "killed" you, uncloak, and backstab.
Comment: This is wrong, you don't speed up to Scout speed when disguising as Scout.
Comment: Are you sure you get a move speed increase while disguised as the scout? This wiki page seems to contradict you. http://wiki.teamfortress.com/wiki/Disguise

Why disguise as scout?


How far back from the final approach fix can you intercept the glideslope?

Question: I was looking for the point that you engage your auto pilot approach glide slope before the final approach fix in this question. How far back can you go?
Comment: It depends on the airport. ATC is required to give you the glideslope intercept altitude for your specific approach when they issue your approach clearance, and that is the altitude that you should maintain until you get established on the glideslope.
Comment: @jwzumwalt One could argue that you should maintain that altitude, but you aren't necessarily required to. When ATC says "maintain [altitude] until established," you are established when you are on a lateral segment of the approach. Once established, you can descend to the lowest published altitude of the segment and intercept the glideslope at that altitude if you wish. (AIM 5-4-6 e 1)
Answer: From the navaid limitations section of the FAA Order 7110.65 (below), it's 10 miles from the transmitter. For the minimum altitude, it's shown on some charts as a lightning bolt.
Answer: Depends upon the approach.  In general for the ILS, the glideslope intercept will be at the approximate position of the outer marker or 4-7 miles from the threshold.


In Windows, download a file from the web to a remote server

Question: For example, there is a file www.domain.com/file.xyz
I do not want to download the file, then upload it to my server.
Is it possible to access the server, then tell it to get www.domain.com/file.xyz to a dir in the server? It the server runs on CentOS, and locally, I'm in windows.
Is that possible? If so how?
Answer: SSH to the Centos server and use wget to download the file?
Depends on what access you have to the Centos server - if your access is limited you might be able to map a drive through windows (if the server has SMB configured), but behind the scenes this will still copy the file via your machine and then upload to the server which may not be what you want (for instance if you are on a low bandwidth link, but the server has plenty then you would want to download directly to the server)
Answer: Jon is correct with wget. The following command will get your file for you directly from the web to the CentOS server:
wget http://www.domain.com/file.xyz

If you don't have wget installed and have permissions to install applications on the server:
yum install wget

Answer: Map a drive to the target server and select it as the location for the download when prompted.
Comment: that still incurs the intermediate download location of the local machine


Magit: Files missing in status buffer when "Ignore all whitespace" is enabled

Question: In Magit I sometimes toggle Ignore all whitespace in the status buffer. This causes files that contain only whitespace changes to disappear. This means I cannot operate on them without toggling Ignore all whitespace and refreshing. Is there any option to change this behaviour?
Answer: Magit just runs git diff --ignore-all-space .... That does not output files that contain only whitespace changes and so Magit doesn't display those either. I think it makes sense for Git/Magit to do that, it's kinda what you requested by using --ignore-all-space.

This means I cannot operate on them

You should still be able to do so. Many commands that default to the file at point (with or without confirmation) instead ask you for a file when invoked while point is not on a file.
So for example to stage a file that only contains whitespace changes move point to something that cannot be staged (e.g. onto "Unmerged into master") and press s as usual and then select the file you want to stage.
Comment: Yes, that makes sense. I can stage it as you proposed and that is fine, but what I think I want is something similar to what `git status` gives me on the command line. Here I can see the staged file no matter what diff options I use.


Keyboard doesn't function after Fedora 17 update

Question: I updated my Fedora 16 installation to Fedora 17 on Saturday, and the update worked without reporting any errors. I carried on working on the machine in question and then switched the computer off.
Last night I went back on the computer, I switched it on and got to the log in screen. At this point I tried to type in my password but the keyboard wouldn't work. I unplugged it (it's a PS/2 keyboard) and plugged it back in. The lights flashed for a split second but the keyboard still wouldn't work. I then plugged the keybaord in to a USB to PS/2 adapter, and the keyboard still wouldn't work.
I restarted the computer and tried to access the BIOS and I was able to do so. So the keyboard doesn't seem to be faulty, it just doesn't work when Fedora boots in to the GUI interface.
I did try to boot in to the "recovery mode" of Fedora, and the keyboard works here with no problem.
As I still have access to Fedora via a terminal interface, is there anything I can do to fix the keyboard problem via the terminal without having to reinstall Fedora?
Answer: I have had a similar problem.
In a terminal try:
<code>sudo system-config-keyboard
</code>
Choose you keyboard language.
That made it correct for me. The only problem I seem to have is that if I reboot, it get reset again.
Comment: I've tried this and it didn't work. I've ended up getting the Fedora 17 disc and replacing the current OS with this. Thanks anyway!


Rear Rotor 2006 Dodge Grand Caravan

Question: I am trying to change the rear pads and rotors on my 2006 GCV and the rear passenger rotor is not coming off. I have removed the caliper but I have not tried releasing any tension that may be caused by the emergency brake. Does anyone know if this could be the cause or if I just need some more brute force/heat to get it off?
Comment: Depending how the e-brake is setup, you may need to release it to get the rotor off.  Some e-brakes are setup like drums INSIDE the rotor.
Comment: The @rpmerf for the prompt response.  I guess that is what I was looking for here, a definitive answer on if I need to try this step.
Comment: I made my comment an answer.
Answer: 2 possibilities.

Rotor is rusted to the center hub, soak center hub with penetrant then take a medium hammer and tap between studs to loosen it from center hub. Some rotors have threaded holes near the studs where you can install and tighten metric bolts to push the rotor off.
That particular model has a brake shoe for the parking brake and it is hidden behind the rotor, it is a combination Rotor-Brake drum, if the brake shoe has worn the drum the shoe may be holding the rotor from coming off, it will have to be pried off gently since there is no way to access the star wheel adjuster until the rotor is removed.
Answer: Depending how the e-brake is setup, you may need to release it to get the rotor off. Some e-brakes are setup like drums INSIDE the rotor.  Others are setup on the caliper to close the caliper.  You will need to see if the emergency brake cable is connected to the caliper or behind the rotor.
I know some dodges in the 90's had the disc/internal drum setup. I am not sure how common that is beyond that.
Comment: FYI, Rear brakes on that model are shoe type for the parking brake, inside the rotor.
Comment: I posted this question on a chrysler forum also and they pointed out how a video on how to release the brake.  https://www.youtube.com/watch?v=TH3eNMfuuBA
Comment: @SteveSalowitz nice video!
Answer: If you have an emergency brake drum cast into the rotor, the emergency brake may not be releasing, on that side. It could be a seized cable, or a seized actuator lever. Have a helper apply and release the emergency brake, while you watch the cable which feeds that wheel. If there is no movement of that cable, and no sound of movement in the drum area, your emergency brake may be failing to release. This is an unpleasant situation, because until that tension is released, the rotor will not easily come off. You'll have to hammer that rotor off, using a 5 pound hand sledge, and then replace the rotor and the frozen cable. Some parts stores will rent you a large three-jaw puller, and if you can find one, you may be able to pull that rotor off the hub, using that method.
If you can see the cable moving, as it applies and releases tension, your emergency brake shoes may not be the issue. The rotor may be frozen to the hub. As others have said, spray WD 40 (or the like) around the rotor/hub connection, and rap on the face of the hub portion of the rotor, repeatedly. In stubborn cases, heat from a torch may be necessary, while you hammer at the hub portion of the rotor, to break the rust seal. Keep a fire extinguisher and clean rags handy, to control flare ups, as the torch hits the volatile WD 40 residue.
Some of these combination rotors are equipped with threaded removal holes, in the face of the hub portion of the rotor. If yours are so equipped, thread a proper bolt into the hole, and gently turn the bolt inward,  as you tap around the rotor with a hammer. This may pop the rust seal between rotor and hub. The name of this game is patience, and persistence.

Rear Rotor 2006 Dodge Grand Caravan


Convincing my manager to use salts

Question: My manager says we don't need to salt our passwords because people are not likely to use the same password because they all have different native languages, in addition to the websites they are active at. What is the best counter argument to this?
Comment: The fundamental problem is that **the least qualified person in the room is making security-impacting decisions**. Fix that problem and the rest will follow.
Comment: You-lose-job-for-being-stupid-ass and you-be-liable-for-billion-dollar-lawsuit are the two arguments I'd bring up. Even salted passwords are not particularly safe nowadays (need to run many iterations of the hash!), but not salting them is outright stupid. Any person insisting on such a thing should be fired and get brandmarked on their forehead to be sure they're never again hired by any other company. It's like saying "our office does not need a fire escape because I don't smoke".
Comment: Your boss is right. Everybody knows that all hackers and script-kiddies are monolingual Nigerians, and that they'll never be able to find English dictionaries for their dictionary attacks. After all, if the Nigerian royals, prime-minister, and generals don't have ready access to current English spell-checking technology, despite the fact that English is their only official national language, it's very unlikely that they'll be able to find dictionaries of other languages either.
Comment: What kind of system is likely to have every user speak a different native language? That sounds like an incredibly bad assumption and/or an incredibly specialized application.
Comment: sort hashdump | uniq -c
Comment: It may be a naive question, but why does the manager care about (ultimately) whether your user table has one extra row or your authentication code has one extra expression? What's his concern, anyway?
Comment: What is that argument even trying to dis'prove'? What effect of using salts isn't needed because of "not likely to use the same password"? maybe the way of least ressistance is to just explain another reason to use salts and leave it at that? Problem is that I don't see what the general argument even is with the languages, so not sure what to pick for a different argument. Maybe rainbowtable-based argument?
Comment: The argument would be that if you don't work without salt out of stupidity, but intentionally after being warned about the stupidity, you might move from civil liability to criminal liability when your password files are stolen.
Comment: @user2357112 Perhaps the system is being designed for the voting round of the Eurovision Song Contest?
Comment: The necessity of salts has absolutely nothing to do with whether multiple users have the same password.
Comment: I'm not sure why this is a problem to begin with. Most web frameworks nowadays comes with user management models that implements salted password, strong hashing, and hash upgrade mechanism, and if yours don't then there's probably plugins for that. What is the business case for not using salt in the first place, when integrating existing solution is much easier than reinventing this tired old wheel for the umpteenth times.
Comment: @user2357112 Send your manager the link to this question. That might help. :-)
Comment: @LieRyan For those reasons I think it's more likely the question is over if a legacy system should be upgraded, not about the design of a new one.
Comment: @TheodorosChatzigiannakis s/row/column/
Comment: @DavidConrad Right! I meant column!
Comment: Although not strictly duplicates, a lot of the discussion has already been covered here: http://security.stackexchange.com/questions/8565/am-i-required-to-hash-passwords/ and here: http://security.stackexchange.com/questions/18783/how-to-convince-your-boss-about-importance-of-it-security/
Comment: Based on comment by @EricLippert, if you can carefully influence the change in who makes such decisions in your org, it will go a long way to the security of your products & services.
Comment: A list of blog posts about the frequency distribution of common passwords might help convince him. Or posts about the consequences of not using salts, like this recent one: http://nakedsecurity.sophos.com/2014/06/24/new-york-city-makes-a-hash-of-taxi-driver-data-disclosure/ Although I doubt that *only* this will turn him over (see the remarks in Tom Leek's answer).
Comment: I want to point out that I wouldn't blame the manager in this case - I blame the consultant who did a pisspoor job of halfsplaining salts to the clueless boss. He obviously heard that explanation from *somewhere*...
Answer: I'm not sure where you are from. First of all his opinion is against the the considered industry best practice as defined by NIST. Furthermore your manager is dangerously wrong. The more users the more likely it is to get the same passwords for several users. Also the following companies do it and I'm quite convinced that they have a larger global user base than your website:

Facebook
Gmail
Linkedin

Also another reason which is something you can explain from a business perspective is the risk of image/brand damage when  you get negative publicity. To give you an example Adobe used a bad implementation for password storage which lead to the same issue as you are having now: the value resulting from hashing (in case of Adobe they were using encryption rather than hashing) the password was the same for several users if they were using the same password (in their case due to not using an IV while performing symmetric encryption, but this is not relevant). This caused a massive storm of negative publicity, after all an internet company should be adhering to something as simple as password hashing no? The financial cost resulting from such negative publicity can be significant.
Also depending on the country where you live and the laws employed, these days the management can be held personally accountable if it is determined that they were negligent when it comes to protecting data privacy (if cracked passwords are used to get personal data of users for instance). Also depending on the type of information stored, financial, medical, credit cards, different rules may apply which can result in other types of fines as well.
This is something which might not be relevant for password hashing directly, but might come in handy if your manager makes further bad decisions. So make sure to make copies of emails where you clearly explain the problem and also save your managers reply. (just to cover your own ass)
The fact that you are not using salts also probably means you are not using a correct hashing algorithm, as these often take care of the generating salts and performing an amount of iterations. The three accepted algorithms are:

PBKDF2
bcrypt
scrypt
Comment: To add to this - if your company has any audit requirements, especially if you are externally audited - I am sure your audit department will have a few things to say (although generally audit is a post-fact function, in this case I recommend you bring them in). Also along with getting documentation (in the form of emails), make sure you print these and file them as part of the documentation of the project itself as this is a major concern.
Comment: You mean as the attached paper if Nist?
Comment: To this list in this answer, I would also add any security book that explains password hashing and show that to the manager, because usually good security resources will only advance salt-based techniques, and list the problems of non-salted techniques.
Answer: The main purpose of salts is to prevent an attacker from saving work by comparing a single calculated hash with all stored hashes. This problem is independent from whether or not the passwords are unique.
Without salts, the attacker can simply go through his list of possible passwords, calculate the hash for each one and then check if the result matches any of the stored hashes. So only one calculation per guess is required.
With salts, the attacker must go through his list for each user, because he cannot reuse the results. This forces him to do one calculation per guess and per user. This massively increases the costs of the attack.
But as Lucas already said, the real problem here is that you're not using a proper algorithm. Salts are only one aspect of password hashing.
Answer: The "best" counter-argument depends on what you are trying to achieve.
If you just want to be scientifically right, then it suffices to say that salts are not, and never have been, a method to cope with two distinct users choosing the same password. In particular because two users who happen to choose the same password is not a problem to begin with, so there is nothing to fix. Salts are for avoiding parallel attacks, including use of precomputed tables. Lack of salts was the capital sin of LinkedIn.
Now being right has an effect only on people who are ready to acknowledge that they may be wrong or at least incompletely informed. What you quote from your manager tends to demonstrate that he is both completely incompetent on the subject, and also convinced that he totally masters it. If you want to convince that manager that he is wrong, then, fat luck on that. What people fear most is admitting, even implicitly, that they said something stupid.
If you want your organization to actually switch to proper password hashing (read this), then what you might be able to do is to convince other people that what the manager just said is pure gibberish, that it does not even make enough sense to be actually wrong. If the manager becomes isolated, he may turn a blind eye on the implementation of proper password hashing, without, of course, ever acknowledging it. There again, the scientifically correct argument is not necessarily the most efficient one. In North America (especially British-influenced areas like New England), business meetings are about avoiding clashes and diluting responsibility, so you should spread some fear, uncertainty and doubt: be sure to point out that your competitors are switching to salted hashes, and not doing the same incurs the risk of losing some market share. In southern Europe, meetings are ritual battles to establish hierarchy, so shout, growl, threaten and use sarcasm to win the crowd support: you don't win by being right, but by being assertive.

One of the most efficient types of arguments, generally speaking, is the appeal to authority. In NIST Special Publication SP800-118 (currently in draft), one can see:

Another example of a hash algorithm weakness is that some algorithms do not use salting.

"No salt" = "weakness". NIST says that. Who is this manager who thinks he is smarter than NIST ?
Comment: +1 for differentiating between being right and convincing someone else.  -1 for assuming you can't convince someone else.  =)  One strategy is to think about how to maneuver the boss into thinking that salts were his or her own idea, and making sure that (s)he can endorse salts without looking like a fool.  Being combative will work against you here; you want the boss to *want* to endorse salts.
Comment: `convince other people that what the manager just said is pure gibberish` I don't think you should talk bad about your manager behind his back!
Comment: yes, do it while the manager is around
Comment: This answer belongs on [workplace.se].
Answer: In a certain sense, if you're arguing about salt then you've already missed the boat. The state of the art with respect to password storage security is well beyond the "to salt or not to salt" question, and has since moved on to counting iterations.
But lets start with basics. Here's an answer I wrote a short while ago that was surprisingly popular. It explains why salt is better, and lots of people have said it made something click where other explanations fell flat. It's more or less what you're asking -- show it to your boss if you think it'll do some good:
Why are salted hashes more secure?
But the important point there is the last one made there. That is, storing a salted SHA1 hash and calling it good is no longer considered responsible. Computing power has hit the point where billions of hashes per second is no longer theoretical, allowing you to blow through the entire 32-bit space of a brute-force attack faster than what it would take to explain what you're doing.
Now the focus is on forcing the attacker to solve the problem thousands or hundreds of thousands of times just to make one guess. That's where PBKDF2 shows up (wearing its NIST-issued suit and tie), as well as scrypt and friends (looking scruffy but powerful).
Which algorithm you choose isn't really the key. They all solve roughly the same problem, just in different ways with different emphases. But you have to use something -- some algorithm that makes it difficult to brute-force even a single password. The reason is simple: It's the industry standard, it's measurably and provably more secure, and there's no significant cost to using it. Put those factors together and it quickly becomes apparent that if you don't do it, then you can be considered negligent in the event of a breach.
Answer: The best argument is to pull out a list of the most common passwords and show that about 1% of your users will pick "123456".  The second-best would be to pull out a password leak analysis for a large site and show that only about half of your users will manage to come up with a unique password.
Comment: The user who choses "123456" is sunk, adding salt will make little difference. - So this is a bad argument, as is any match from the top 100  passwords.
Answer: You should make two points:

Using a salt reduces the value of a stolen file containing hashed passwords. This is true regardless of what language(s) are spoken by the users of the system, because an attacker who has a rainbow table for your hashing algorithm can use it to reverse the hashed password irrespective of the native language of the person who chose that password.
Using a salt is almost free. It gains you almost nothing to exclude it, and even in your manager's current estimation excluding it is only "likely" to not cause a serious security problem. Therefore, use it.

There is an objection that your manager might raise against the first point, but I hope cannot: "we are using our own custom hashing algorithm, so there is no danger that a rainbow table exists for it". In that case, you must also make the case for using a standard password-hashing algorithm.
I also find:

[the users] all have different native languages

to be a bizarre assumption to make about a system. If you rely on an assumption for your security analysis, then your system becomes insecure (or at any rate, not assessed for security) as soon as the assumption is broken. So having relied on this assumption for security, you then need to enforce that no two users of the product have the same native language. Why on earth would anyone want to restrict their system in that way, and in particular how is enforcing this restriction going to be easier than using a salt?
However, in this case that assumption doesn't even lead to the conclusion your manager makes that salt is unnecessary (for the reason I give above). So the question of whether the assumption can be maintained is fairly irrelevant in the face of the fact that it doesn't help!
Finally FYI, there's a specific reason why my first point above contradicts your manager's analysis:

not likely to use the same password

is a flawed analysis of the weakness that salt addresses. It doesn't matter to the attacker whether two users of the system have the same password or not, unless the attacker just so happens to be one of those two users and therefore knows the password that they share. Salts do not only defend against this attack, they also defend against rainbow table attacks. So even if this unusual same-password attack by one of your users were impossible on your system, you would still need salts.
Answer: I guess this is more a people problem than a technical issue. Therefore you need to respond with soft skills rather than technical explanations. If your manager reacts positively on technical explanations, choose one of the answers before.
If you want to go the soft skills side, you can try a few things:

Most important to remember: your boss is your boss. Do not get angry against him, otherwise you'll be the unlucky.
Try not to ask him questions which he can't answer. Instead ask indirect questions in form of simple sentences.
Try understanding his standpoint and arguments.
Apply paraphrasing.
Never laugh.
Never be impolite.
Read Dale Carnegie's book "How to win friends and influence people".

A sample dialog might look like this (be aware that I'm not a native English speaker):

Boss: "We don't need salts."
  You:  "We don't need that additional protection."
  Boss: "Yes, our users don't reuse the same password."
  You:  "Strong password are already secure."
  Boss: "That's right."
  You:  "Alright, I understand. Our users make the password secure and we just live without salts."
  Boss: "Yeah, maybe not all users ..."
  You:  smile

Or like this:

Boss: "We don't need salts."
  You: "The benefit of using salts is not worth the effort."
  Boss: "That's correct."
  You: "So we deleting the salt from the task list and go on with the rest."
  Boss: "Right, we're already behind schedule."
  You: "If we would meet the schedule another way, can we would implement the salt."
  Boss: "No, I don't understand that salt concept."
  You: "That cryptographic stuff is always hard to understand."
  Boss: "Even when I read an article, I didn't get the clue."
  You: "Which makes you think it's a lot of effort."
  Boss: "Yes, we'll lose two days or so."
  You: "With some help of a framework I can do it in 2 hours."
  Boss: "Really?"
  You: smile

Note that there are no question marks at all. The boss is never under pressure of answering a questions which he might not know the answer to.
Unfortunately it's quite hard to apply such techniques if you never did before.
If this approach doesn't work well either, there's one more option:
Just implement it. It shouldn't be too much effort and your boss will probably not notice it, except he's doing code review or looking at database tables.
Comment: If I were in the OP's situation, I certainly wouldn't be confident I could guide the boss to the correct conclusion this way. We nerds aren't generally known for our verbal jujitsu skills.
Answer: Just throw some hashs (maybe his own password) into Google. Most likely it will return the password. His weak hashing is like no hashing at all.
https://www.google.de/search?q=a94a8fe5ccb19ba61c4c0873d391e987982fbbd3
If that does not convince him look for a new job...

Convincing my manager to use salts


Entitlement to a British passport

Question: My girlfriend's mother was Ghanaian, her British father died about 15 years ago. She is 36 and lives in the USA. Is she entitled to a British passport because of her father?
Comment: To make this more "interesting", there was a rule change in 1983; if your girlfriend was born in 1982 or earlier different rules may apply. See for example https://expatriates.stackexchange.com/questions/12251/apply-for-british-citizenship-under-a-british-mother-born-before-1983?rq=1
Answer: Your question is really about British citizenship because someone can only get a British passport if they are already a British citizen or other British national.
You didn't give enough details to determine whether she is currently a British citizen. I can give some situations in which she would be a British citizen from birth.
If she was born in the UK, she is a British citizen.
If she was born outside the UK, and her father was a British citizen at the time she was born, and specifically he was a British citizen "otherwise than by descent" (meaning he was not himself born abroad and got citizenship from a parent; if he was born in the UK or naturalized in the UK then that would be okay), she is a British citizen.
Answer: legitimate descent from a CUKC father for children born elsewhere. Only the first generation acquired British nationality automatically. Second and subsequent generations could do so only if born outside the Commonwealth (or Ireland) and registered within 12 months of birth or if the father was in Crown Service.
Answer: I agree with the previous answer. Firstly, you need to be a British Citizen in order to be eligible for a British Passport.
In case, your girlfriend doesn't have British citizenship then she will have to apply for a Certificate of Naturalisation which has specific eligibility criteria to fulfill like - must communicate in English, must be of good character and others.
Comment: This answer is as unclear as the question. If she is not already a British citizen, she may have to go through the process of naturalization, not just apply for a certificate. There is also a slight possibility she might be able to register as a citizen, but that depends on information we just don't know.
Comment: Naturalization as a British citizen requires, among other things, intent to continue living in the UK. She lives in the USA.

Entitlement to a British passport


Is it possible to implement VSLAM on Arduino?

Question: If not, then which microcontroller will be suitable?
Answer: Not on nano and uno because of memory size. Really basic one with a low-resolution image and slower fps might be possible on mega. Still memory size might not be enough. Due is really marginal in acceptable processing speed with a low-resolution image but still have a memory problem. Just have a look at how much memory you need to store 2 or 3 images on your ram. That is the marginal ram requirement. You can use an external storage module which will take minutes to process a single frame.
Choose a board with more than 1.0GHz cpu, 128Mb ram with linux.
Answer: If it is a real-time SLAM for some real application I would say yes, it is impossible. You won't be able to process 30 fps on your arduino
go for the latest Raspberry or Odroid or a similar SBC


What's a realistic distance to expect boys aged 11-17 to sea kayak in a single day?

Question: I'm thinking about taking my Scout troop (boys aged 11-17) on a sea kayaking trip.  What expectations should I have for the distance that we can travel in one day?  Assume good weather (clear skies, very light winds, and calm seas).
Comment: Along with question - due to varying ability's I would suggest a mix of double and single kayaks - doubles are great as they reinforce many Scouting values and support the weaker boys. If (when - they are boys) they get competitive two weaker boys in a double will give a strong boy in a single a run for his money. I would be prepared to plan further/longer if they (especially weaker boys) were in doubles than singles.
Comment: Are you going out on the ocean, an inland sea, or lakes?
Comment: Ocean.  We'll be traveling parallel to the leeward side of Catalina Island, off the coast of southern California.
Comment: I second what @mattnz said. Also on the many trips I've done with similar age groups with little to no experience, I tend to go by an average of 1 mile per hour pace. This has served me well. It allows time for the weaker paddlers if you must make a destination by a certain time, but if you have a quick group then you have some extra time at stops / points of interest / camp. Yes it's slow, but it can be fun to make yourself slow down.
Answer: If you don't know what your boys are capable of then it's unfair to have expectations.
I'm a Venturer Scout adviser for Scouts Canada; I take boys in that age group on trips regularly. I don't know what your group is like, but if it's anything like mine, then the boys probably all have different levels of ability, strength, and skill. For trips like this one, you can only go as far or as fast as the slowest boy. My experience has taught me that you can't realistically set goals for distance unless you already know what your boys are capable of.
Before you even plan your trip, I would recommend that you plan a day or two of kayaking just to see what your boys in fact can do. Don't plan on covering a certain distance, just plan on being on the water for a certain amount of time. You can then use this time to answer your own question by keeping track of their progress over a certain amount of time or distance. It's important make sure that your boys also have a firm grasp of basic skills, and how to respond in case of an emergency. I always take my boys to a local lake just to have them paddle around together before I'll consider taking them on trips. I give them all a quick instruction, then let them play for a bit while I observe so I can get a sense of what their natural ability levels are. I'll get them to play games too; races are a good way to separate the fastest from the slowest. If you're using two-person kayaks, this can help you balance the group by pairing the stronger paddlers with the weaker ones.
If you know you won't have an opportunity to assess your boys before you take them on a trip, then you need to either plan a trip that anyone of any skill level could accomplish, have more than one plan in case Plan A doesn't pan out, or supplement the trip with other activities. South California is obviously different than up here, so you probably can't just tell the more adventurous boys to paddle off and explore a nearby island while the exhausted boys hang out by the fire and rest their aching arms, but you could perhaps have them paddle to the horizon and back, or have them create an obstacle course where they paddle to a point and back, then sprint-portage the kayak down the beach, and paddle to another point, etc...
I gave up having expectations without experience a long time ago. Get to know your boys, have them set goals, then let them have the expectations.
Comment: As it turns out, we're going to go about a mile.  We'll see how long this takes, and use this as measuring stick for how far we may be able to go in the future.
Comment: @MarkS - Sounds like an excellent plan.
Comment: Seconded everything here, especially the advice to have some additional activities that can expand to fill any leftover time.  It's much easier to put young people off an activity by overdoing it than by giving them too little, and novices of all ages can spend a lot of time enjoying paddling in circles to chase each other.  So keep it short, and have a spare plan that adds a detour to lengthen the trip if you need it.
Answer: Most grown people are good for an hour or two of constant paddling. Children get bored more quickly then they tire. People who go farther are either more athletic or more disciplined. I go fishing in my kayak, and my fishing grounds are about an hour's paddle each way (depending on currents and wind), and I spend an hour or two trading between drift fishing and paddling back up current again.
 At the end of that, I am pretty worn out, my butt hurts and I don't feel like doing anything at all physical after that. Sometimes catching a fish is a curse when you get back and have to bend over and clean your fish.
In addition to what Shen wrote, first drill then in self rescue, spend a whole afternoon on it until the boys can slip back into their kayaks like otters. This is perhaps the most important excersize/drill you will do before bringing anyone out on the water deeper than they are tall. I drill with my kids the beginning of EVERY summer before we go paddling anywhere. Self rescue, swamping kayak or canoe, any of the rescue type scenarios including pretending you got knocked out so they can rescue you. Thankfully my kids think it's fun.
Answer: On a sea kayak you might get significantly better results but my 9yr old could maybe do a mile on our rec boats.
Answer: I paddled from Zürich to Amsterdam with no experience in kayakhiking, the following rule was pretty accurate for me.
But before i get into that rule you have to do a testrun to see how far you can go in one day (preferably on the same type of water you plan to paddle on like a river or a lake).
Here's my rule of thumb.
If it is a river:
hoursYouPlanToPaddle * (velocityOfRiver / 2 + distanceYouCanCoverPerHour) = distanceYouWillCover

If it is a lake:
hoursYouPlanToPaddle * (distanceYouCanCoverPerHour / 2) = distanceYouWillCover

Now this is certainly not a scientific Formula, but it gives you a good idea of how many kilometer you can cover, and you're still prepared for unexpected timekillers like kids having to pee, breaks and other hurdles you have to overcome when travelling in a group.
And i think this fits a Family which have no intentions to be stressed out the whole day because you're not quite there where you should be.
Nonetheless be sure to make a oneDay journey first, and in reality you could encouter strong winds or currents which make you slower and cost alot of power, which is why you should be generous with shortening the distance per Day, it's not half as being able to skip a destination then not arriving there
Answer: In a 3 meter racing narrow beam double outrigger. Most kids can hold there walking speed on long tips. In the bay. That is not pushing it.  Kayaking is a wider boat but no outriggers. So figure 2 mpr. or a 15 mile trip. For the day. 2 in a boat add 1mph to that or 20 miles. That leaves time to shore lunch. Most kids here can do that easy.