Why are electrons not pushed out from the conductor at an open circuit under the influence of a power source?

Question: Frequently, electric current is compared with water flow. For example, if I make a hole in a water tank, water will flow till the tank pressure and the atmospheric not become equal or the tank becomes empty. Why does this not happen with electricity?
Comment: It does if the voltage is high enough to break down the insulating effect of open air. That's called lightning ;)
Comment: Because that's the definition of an open circuit.
Comment: One way to think about this is by taking the energy into account. When water flow pushes out of an open pipe, it "goes towards" a lower energy. On the other hand, electrons in a circuit are in a lower energy state, compared to free electrons. So while water dripping from a pipe loses energy (gravitational potential energy), electrons would need to *gain* energy in order to be freed - imagine a water flow pushing against a hill. The thing is, the hill is ginormous in the "open circuit" case :)
Answer: You're imagining an open circuit to look like this:

A better analogy would be this:

The pipes in a circuit aren't surrounded by free space for the water to flow -- they are tunnelled through a rock. Where there is no pipe, there is just rock and the water does not flow.
Comment: If you're using water to visualise how electricity works, it's also important to remember that the "circuit" (pipework) either lies flat, or is in space where there is no gravity.
Comment: Good visualization. More wordy: the energy barrier for electrons to "leak" is extremely high, and only occurs when the "pressures" (voltages) are extreme or when they are (stretching the metaphor now) "boiled" away by incoming photons via the [photoelectric effect](http://en.wikipedia.org/wiki/Photoelectric_effect).
Answer: The water analogy is very limited and does not model the way electrons move in a wire. It should always be used with great care.
Electrons drift very slowly (about 1m/hour) by jumping from atom to atom. Current appears to flow instantaneously in a complete circuit but will not flow in an incomplete circuit (no electric field to move the electrons).
Inside a wire the conductivity is high (lots of 'free' electrons buzzing about randomly) and a small electric field (a voltage difference at each end of the wire) can produce a current. Outside the wire the conductivity is very low and there is no electric field to overcome the attraction of the positively charged metal ions in the wire should an electron leave the surface of the wire.
Water (molecules) on the other hand will simply flow out of the end of the pipe because the force pushing the water in at the open end (due to air pressure) is less than the force pushing the water out of the system (air pressure + gravity + pump?).
Water can escape because the inside and outside of the pipe is essentially the same medium and the molecules are acted upon by pressure (air and pump) and gravity (inside the pipe) and gravity (outside the pipe).
Is it possible for electrons to escape the wire?
Yes.
For electrons to escape their 'metal container' there must be sufficient energy supplied to break the bonds that tie them to the metal ions. This can be done with high energy photons (see photo electric effect and work function) or heating the metal (thermionic emission). Of course if this is done in air the electrons can't get very far before being absorbed so it needs to be done in a vacuum.
If the electric field is very high (as in charged clouds) the resulting spark is lightning.
Comment: Hi Jim,  Just to be clear the drift of electrons in a metal due to external E fields can be slow.  But the thermal motion is very fast.  (something like 1/2mv^2 = 3/2 kT say v^2 = kT/m I get ~ 2x10^5 m/s assuming an effective mass of 1.)
Comment: @GeorgeHerold absolutely correct and thanks for clarifying (+1). I've tried to avoid getting into maths details over thermal motion (fast, random movements in all directions but essentially net zero movement overall)  vs drift velocity (slow migration in hops in the general direction of the applied field).
Comment: @asawyer You need to think about the wave, not just the individual particles. When you push on a stick, (almost) the whole energy of your push will be transferred to the other side, even though the atoms on one side didn't move all the way to the other side - the energy was propagated in a wave *over* the electrons and atoms, without having to move them too much. A bad but fitting analogy would be Newton's craddle.
Comment: I have a question - If electrons move so slowly how do so many of them (6241,509,324,000,000,000 per amp per second?) move to create the current?
Comment: @Luaan Ah ok that makes perfect sense.
Answer: Making a hole in a water tank so that water can escape is the same as a short circuit in electronics. Blocking a water pipe is the same as open circuiting a connection.
Remember, the water tank is a "water flow insulator" and is the same as a blocked pipe.
Answer: It's all a question of pressure equalization.
With the water it's not the water's pressure that is equalizing, but the atmospheric pressure acting upon the water.  The air pushes down on the water and pushes it out of the hole until the inside and outside pressures are equalized.
Connect a wire between two poles of a battery and the pressure between the two poles can equalize.
Stick a bung in the hole of the tank and the water can no longer flow - the pressure difference between the inside and the outside is now fixed.  Add a very high resistance between the two poles of a battery and the current can no longer flow (or flow very slowly - the bung has a drip). The higher the resistance the slower the flow.
Air has a typical resistance (according to Wikipedia) of around \$1.30×10^{16}\Omega/m\$ to \$3.30×10^{16}\Omega/m\$, with a breakdown voltage of around 300kV/m (which is the pressure at which the bung gets forced out of the hole in the tank).
Answer: Water and electricity don't work the same way.  Sometimes water in pipes is used as a analogy for current in wires, but that analogy breaks down in the case you are asking about.
Actually the analogy is still valid if you remember that air doesn't conduct electricity, but air conducts water flow easily.  To make the water flow analogy more accurate, you'd have to envision everything except the interior of pipes to be made of some solid material.  Imagine everything that is air actually being some hard rubber, for example.  Water wouldn't flow out of a open-ended pipe because it can't go anywhere.
Answer: Energy Levels
This effect is usually explained by the concept of energy levels. The materials are divided into three groups: insulators, conductors and semiconductors.
For conductors...
From the point of view of energy levels (atomic), for the conductors, there is no energy gap between the valence band and the conduction band. Then, with very little energy, the electrons can be set in motion.
For insulators....
For insulator, the energy gap between the valence and conduction bands is much larger, which means that a lot of energy is needed to locate an electron in the conduction band.
Then, in a open circuit...
In an open circuit, the insulation surrounding the conductor has a much higher level of energy than these. Under normal conditions, electrons from the insulated conductor, do not have enough energy to reach the conduction band of the insulator.
But...
However, if the energy applied to the conductor is increased significantly, it can achieve a jump to the insulating material; this effect is electric discharge or dielectric rupture.
Comment: Thank you. Great answer. Nevertheless, it did not help me.
I understand why there is no current in dielectrics. According to my idea of the electric current electrons must be pushed to the outside world of the conductor. But they abut against the end of the wire as in barrier. What keeps the electrons inside the material when the electromotive force acts on the conductor?
Comment: @user3131972 Think about it: how electrons move from one type of conductor, to another type, e.g from copper to aluminium? They can move because the energy level of electrons in copper match the aluminium (aprox). From conductor to insulator, the energy levels are so much different, then for the electrons go into the insulator, we must provide a very much energy.
Comment: @user3131972: There is no "outside world" per se, there is only "something else". In this case the "something else" is the insulator called "air".
Answer: Electrons are trapped in a metal because of the work function of that metal.  The work function is a measure of the energy of the electron in the metal to it's energy in free space.  (or in the vacuum.. the presence of air is just an added complication.)  The electrons in a metal are always in a lower energy state than the vacuum state.  If a strong enough electric field is applied to the metal the electrons can over come the work function and leave the metal.  (think about a vacuum tube cathode.)   A water analogy is fairly easy.  Water is in a bucket or trough with tall sides.  (But it's better to just think about real electrons.)
Answer: Any difference between the number of electrons in a particular region and the number of protons in that region will cause nearby electrons to be attracted or repelled as needed to equalize the numbers.  The only reasons electrons would want to leave a region would be either that there were too many electrons in the region relative to the number of electrons, or that a nearby region had a shortage of electrons (relative to protons).  A "perfect" one-amp power supply will move one coulomb of electrons (that's a rather large bucket load) from one terminal to the other every second.  If no electrons leave the terminal which is receiving all those electrons from the supply, it won't be long before the electrons get so overcrowded that they'll start to leave even if that would mean the place they're going would be somewhat overcrowded (since it would be less overcrowded than the place they're leaving).  Likewise, if no terminals enter the terminal from which the supply is taking the electrons, its electron shortage will quickly become severe enough to cause it to start grabbing electrons from anything nearby, even if that would cause an electron shortage nearby (since it would be less dire than that of the terminal that's grabbing the electrons).
As electrons leave one terminal and enter the other, this will reduce the urgency with which those terminals will need to expel or acquire electrons.  Note that in relative terms, it takes an amazing small surplus or shortage of electrons to create an essentially irresistible force.  The mass of electrons in a conductor cannot quite be viewed as incompressible, but it's very close.  In very rough relative terms, if a typical material had a swimming pool's worth of electrons, the difference between a severe shortage and severe overcrowding would be less than a drop.
Answer: Imagine this:
For electricity, the pipe heals itself.  The wall thickness is the distance to the nearest other conductor.  It may seem kinda weird to think of moving things through a solid pipe wall like a wire through air, but if you ignore that part of physics, the analogy works.
If the "wall" is too thin to hold the pressure, it punches through, which we call an arc.  This works at very small scales too, like a 5V chip arcing internally when powered with 12V.


How to deal with client's staff that says "this will be easy"

Question: I am an external project manager. The internal staff at a clients business have started making comments to the effect that "this requirement will be easy to deliver". Such comments are damaging our relationship with the client. The comments are completely unfounded as the people making them have no expertise in the relevant areas. Nonetheless the comments are creating unrealistic expectations in the client's mind regarding the speed of development. I don't want to make an enemy of the staff saying the things are wrong but also want to stop the staff creating unrealistic expectations. I have told the people that such comments are unhelpful and wrong but they still persist. Do you have any suggestions on how to manage this situation?
Comment: My, politically incorrect, response would be that if the work were really that easy, they wouldn't need me, because they could do it themselves in between their other work.
Comment: Why exactly is saying "this is easy" damaging your relationship?
Comment: Does not really help with the fact that I said I don't want to make an enemy of them.
Comment: @Erik the comments are harmful because they are creating unrealistic expectations in the client's mind
Answer: The first counter to 'this requirement will be easy to deliver' should always be ask politely to list down the risks involved. Such unfounded claims are done by people who want to boast or want to challenge the team off a cliff.
The art of war in such situation is to transfer/overload ownership by asking counter specific (not open-ended) questions to the point where they have no answers. The point is to ask questions that will test their knowledge and not questions that have generic answers.

"It seems you are well aware of the design as well as low level
  implementation involved to achieve this requirement. Can you please
  list out the design considerations we need to make so that it can be
  achieved as easily as you mention?"
"So what are the risks involved in implementing this?"
"So you're saying there is no risk involved since it's fairly easy to
  implement? In our current system/application can you show us a similar
  risk-free implementation?"
"How closely have you worked on functionalities that deal with the
  integration part of this requirement?"
"Can you please guide/elaborate on the integration/testing effort
  involved and how you propose to overcome the challenge of ___________
  ?"
"What are the architectural components that will be impacted by this
  implementation?"

If they counter with a question, simply be surprised and say

"WE were hoping you would answer that since you found the requirement to be easily implementable." ...or... "WE thought your expertise was in such implementations and you would guide us all."

And then immediately, steer the discussion or conclude with that statement that

"I believe there are still few unanswered questions and risks to
  identify, so this requirement estimate needs to be reconsidered. I'm
  not saying it's easy or difficult or impossible, all I'm suggesting is
  that we take a measured approach to understand the risks involved, have discussions necessary, get X, Y and Z involved and then proceed."

By saying so, you set yourself at a neutral mature position, establish control over defining the estimates and the direction of the conversation.
The aim is to deter future claims and by counter questioning detailed level aspects of implementation, you corner individuals who make baseless claims. Continue to relentlessly question them until they back down from making such claims.
Comment: I'm curious - why are the first two 'we' and not 'I'? Seems to me that you're speaking for someone else, there.
Comment: When you use 'We' it creates a the argument considering with the presumption everyone agrees to what you are saying unless someone challeges/opposes you. Also you want the person who is making baseless claims to perceive the statement as him/her opposing the team's views instead of just your view.

Another reason 'we' is important is because you are taking responsibility and speaking in the best interest of the team and not just yourself.
Answer: What you need to uncover is the driver behind the 'this will be easy' rhetoric.  Is it innocent optimism?  Is it designed to keep sponsors interested in funding this project?  Or is it designed to insulate themselves against a risky project such that they can point to another group or individual--such as you--when and if the project goes south?
No matter the drive, communication is your ally here and what and how you communicate will depend on the driver of this statement.  If optimism, use it to your advantage.  Optimism has a lot of benefits.  Frame your risks and issues you are facing in such a way that keeps this optimism a live.  If they have a sponsor issue, then you need to frame the risks and issues you face in such a way that sponsors do not get scared and back off the project.  You need to support your client with messages that the team can weather these storms.  And if it is the latter, then you need to communicate early, often, very clearly, and non emotionally the facts of what's going on, the risks you are predicting, the issues you are experiencing, and your plans to mitigate and recover.  And you need to document everything so as to insulate yourself if fingers start pointing in your direction.
Answer: What's easier? To eat an elephant or a hamburger?
It doesn't really matter, as you eat both one bite at a time. The difference is how many bites you have to take to accomplish each task.
So, break down your project into specific tasks, identifying the parts of the work that will be more complex that the client might have overlooked. Stress the external dependencies you might have and the pitfalls that could convert silly tasks into weeks long work. The client may be requesting an Iceberg implementation, make sure he's aware of what's down the water.
Bottomline: A single task has different points of view. Put yourself where the client stands and explain the work in the background he's not seeing.
Answer: on agile scrum , having easy/moderate/difficult sort user stories is indica-tion from clients on regular meetings. A product owner will having quick answer for these sort queries with onshore stakeholders .
Comment: at our latest project OEM activation having short easy , mid size moderate , long difficult  stories point . that will a clean direction from project manager to stakeholders on these sort queries .
Answer: Some of these clients might not be having any intent of challenging you or your decisions. It might be just because they are actually ignorant and genuinely think that it is possible to get it done quickly. I have faced this situation a lot.
A project manager also need to be a good people manger. In these kind of situations give your client representative the benefit of doubt. Here is what has always worked for me positively.
I usually subdivide the task at hand into multiple sub tasks and assume the hours needed for each sub task and share it with the client. If at that point of time i am not aware of what goes into it, i politely tell them "I will look into it and get back to you with the specifics..Lets hope we can easily wrap it up".
Client are humans who pay us, which gives them the feeling of superiority. Lets let them keep their ego high and milk the cow slowly.
Answer: The first and foremost way to handle this situation is to explain the development effort in a proper way. Nothing is easy unless a brilliant effort is put into development. My thought is to share the development effort involved with highlighted QA , analysis and development costs.


Android app : Handling app request posted on Facebook

Question: I went through various Facebook tutorials to handle Facebook integration into Native Android app and have achieved success implementing all flows including Facebook login, fetch user details, Share, Select friends.
I am stuck in use case wherein app invite request sent by one user is handled for recipient.
Problem statement: Facebook Send request  tutorial explains well on sending app request to friend which works fine for me as i can see success response as below.
fbconnect://success?request=<request ID here>&to%5B0%5D=<userID>

But the next step is to handle the request. As per tutorial, once recipient user opens up the Facebook for Android app and tap on the notification (I am seeing under top left menu -> Apps section), the app is launched using intent containing request data which can be pulled as below.
Uri intentUri = getActivity().getIntent().getData();

Further request ID (one or more) can be fetched as below
String requestIdParam = intentUri.getQueryParameter("request_ids");

In my case, Facebook app launches installed app but intentUri (statement listed above) itself is returned as null. Hence i can't proceed further extracting request details.
Note: i could confirm that posted request contains complete info e.g. data using below method by passing hardcoded requestID obtained while posting (after logging into app as recepient user).
private void getRequestDetails(String inRequestId) {
        Request request = new Request(Session.getActiveSession(),
            inRequestId, null, HttpMethod.GET, new Request.Callback() {
                @Override
                public void onCompleted(Response response) {
                Log.d (TAG, response.toString());
                }
            });
        // Execute the request asynchronously.
        Request.executeBatchAsync(request);
    }

An early help/pointers will be higly appreciated. Also, is there a way to query pending app requests through Facebook API rather than invocation through Facebook native app intent invocation.
Comment: I would appreciate if someone can share pointers to debug the issue. Thanks.
Answer: This is Facebook bug. Just add Mobile Web in App Dashboard and you will get request_ids


Why would a process be showing an outbound connection from a 169.254 address when there's no unconfigured adapter?

Question: I have a system that has several network adapters, only one of which is enabled. That adapter has ipv4 only enabled and it has a single IP address. It was previously part of a team. The team was broken while trying to fix another issue with the system. Now that it's back online with one nic and one IP address, some of the applications on the system are not working and when I use TCPview to see the connections the server is making I see that the applications in question are connecting on a local address of 169.254.x.x even though there are no unconfigured adapters. The applications that are working connect out via the hostname of the box.
Answer: Sounds to me like those applications are trying to bind to the no-longer-existing NIC team, which is why they're picking up the link-local address.  "NIC" they're trying to use doesn't exist, therefore doesn't have an IP address, therefore generates a link-local address.
Comment: I might have to remove the devices entirely from the system, because again, they're already disabled. I can't imagine how an application is getting an auto configure address from a device it can't see anymore. There's no teaming configuration application running either. When I configure the enabled adapter, teaming is def disabled.
Answer: It looks like there was still some residual issue with the adapter being teamed. I disabled everything except the essential items in the connection properties:
Client for microsoft networks
IPV4
File and printer sharing
Rebooted the server and the TCPView no longer showed the strange connections.


Is the Catechism of the Catholic Church considered scripture?

Question: Is the Catechism of the Catholic Church considered scripture? Does it have the same authority as the Bible? If not, what is its place in the church? Is it considered heresy to preach or believe something that is in contradiction with the Catechism?
Answer: The immediate answer is "No, it is not scripture." Scripture is scripture and adding to it or subtracting from it is a no-no.
As to "Does it have the same authority as the Bible?" Well, I suppose the answer is "authority for what?" For some things the authority of the Catechism is superior (certain areas of theology are only hinted at in the Bible). It can be safely said, though, that there is nothing in the Catechism which contradicts the Bible (if the Catechism is taken as a whole and in light of a Catholic understanding of Scripture).
Can you contradict the Catechism without being called a heretic? That depends on how you contradict the Catechism. On certain matters it is more definitive than others and on some matters it is 100% correct. On other matters it is a bit more theologically ambiguous. It is important to remember:

This catechism aims at presenting an organic synthesis of the essential and fundamental contents of Catholic doctrine, as regards both faith and morals, in the light of the Second Vatican Council and the whole of the Church's Tradition. Its principal sources are the Sacred Scriptures, the Fathers of the Church, the liturgy, and the Church's Magisterium. It is intended to serve "as a point of reference for the catechisms or compendia that are composed in the various countries". (CCC 11)

That word aims is important, because it is not a perfect synthesis and there are many, many finer points which can be debated and there is quite a bit of room for disagreement (you are talking about a Church which has a 1400 year old debate with its neighbor over one word). And it even testifies the the fact that it has not gotten everything perfect for all times and all people:

By design, this Catechism does not set out to provide the adaptation of doctrinal presentations and catechetical methods required by the differences of culture, age, spiritual maturity, and social and ecclesial condition among all those to whom it is addressed. Such indispensable adaptations are the responsibility of particular catechisms and, even more, of those who instruct the faithful:

Whoever teaches must become "all things to all men" (⇒ I Cor 9:22), to win everyone to Christ. . . Above all, teachers must not imagine that a single kind of soul has been entrusted to them, and that consequently it is lawful to teach and form equally all the faithful in true piety with one and the same method! Let them realize that some are in Christ as newborn babes, others as adolescents, and still others as adults in full command of their powers.... Those who are called to the ministry of preaching must suit their words to the maturity and understanding of their hearers, as they hand on the teaching of the mysteries of faith and the rules of moral conduct. (CCC 24)

All of that said, it is very difficult to contradict the Catechism without contradicting some important and definitive doctrine.
I know of one place, for example, which is phrased very poorly (in an attempt to guide pastors to a more compassionate action). My disagreement is perfectly acceptable and reasonable (as I agree with the teaching but not the admonition which goes along with it). On the other hand, if I were to disagree with the teaching behind the phraseological error I actually would be contradicting some very authoritative doctrines in the Church. That would be, at a minimum, a form of heresy.
Comment: Agreed whole heartedly, it's pretty annoying when parts of the CCC are so terse or so vague that itis impossible to read them aloud and have anyone hope to comprehend what you're talking about, yet another reason the CCC isn't scripture, it'd be awful hard to proclaim!
Comment: Part of me really likes the fact that the CCC is so vague -- it leaves more room for future interpretation and exposition.
Comment: I just randomly picked up [this book from a used book store](http://www.vatican.va/roman_curia/congregations/cclergy/documents/rc_con_ccatheduc_doc_17041998_directory-for-catechesis_en.html) which explains the need for local catechisms. Looks hard to read on the website, but it's a pretty good book, especially for catechists.
Answer: According to Catholicism, the Catechism has the same authority as the Bible, its existence is borne out of the same body of folks who brought you the Bible as a compilation of revealed truth in the first place.
However, it can't be conisidered a substitute for the Bible and no, it's not scripture any more than the Evangelical Councils were scripture.  It is the the synthesis of Magesterial Teaching, tradition and scripture.  It owes its existence  to synods of Bishops following the Second Vatican Council placing an emphasis on general Catechesis.
Any Catholic will tell you it belongs right next to your Bible because there is no book which gives so lucid an explanation of the faith. But, it didn't exist until the 1990's so... The more fundamental question is, does preaching against the doctrines of the Catholic Church make you a heretic?
The Catechism is a 'sure norm for teaching the faith' and a 'valid instrument for ecclesial communion'. It's used for teaching directly, and for adapting down to particular catechisms (YouCat, Adult Catechism, Rite of Christian Initiation for Adults (RCIA), etc...). So, one caveat in the Catechism is that it is catholic (i.e. universal)  and it does not adapt the doctrine adequately to particular cultures, ages, and spiritual states of the reader and as such there may be reasons for emphasizing certain aspects of authentic Catholic Doctrine that may at first seem at odds with the Catechism, I think this happened recently with the YouCat, which was geared towards the under 30 crowd and had more concrete answers to questions about sex and money that you'd get by reading the Catechism. Therefore, you wouldn't automatically be a heretic if you preach something that only seems at odds with the Catechism, it really has to be at odds with the totality of Catholic Doctine. If you preached for birth control or abortion or same sex "marriage" or euthanasia or divorce you would be on your way I becoming a heretic, but you'd have to persist in your heresy to truly be a heretic. If you completely give up the faith, then you're an apostate and if you preach something that just isn't very Catholic, like "the Pope isn't very smart" then you're a schismatic. But, if you were never a Catholic to begin with, then you can't be any of these things.

Finally, because I just read it and I don't know whether you want to know this, but the General Directory for Catechesis says:

the catechism of the catholic church is not the only source of Catechesis, since as an act of the Magesterium, "it is not superior to the word of God but at its service." However it is a particularly authentic act of interpretation of that word, such that the Gospel may be proclaimed and transmitted in all it's truth and purity.
Comment: +1 "But, if you were never a Catholic to begin with, then you can't be any of these things." That gave me a good laugh.
Comment: Well you can be in your own church if you want to. I think it's about time Catholicism got its own namespace so we wouldn't have to argue over the meaning of words like Ordinary and Common
Comment: I meant heretic.vatican.va


A Couple of Hearts Probabilities

Question: Here's what I don't get.  I've played a lot of Hearts for many years - thousands of games I'm sure.  The number of times I've played a low heart, and the trick has gone 2H, 3H, 4H, 5H seems way out of probable reality.  But the number of times I've seen all four players play the any of the same value card (e.g. 6C, 6D, 6H, 6S) is once.  Why is the probability of 2H, 3H, 4H, 5H any lower than any 4 same value cards?  In my naiveté it seems that in both cases, the probability calls for 4 players to have a specific card at the same time. Can anyone explain it to me like a 4 year old?
Comment: http://xkcd.com/1364/
Comment: The fact that you see 2H, 3H, 4H, 5H seems surprising. If the player stuck with the 5 is trying not to accumulate hearts, I'd expect that player to slap down the largest heart card he has. If he's trying to shoot the moon, then the 5 makes sense.
Comment: I'm pretty sure most 4 year olds don't understand probability either.
Comment: Sorry for not being clearer - the cards most times do not appear in that order but more likely 5H, 4H, 3H, 2H or some other combination started by the 4H or 5H.  Thanks for  your comments
Answer: The reason H2,H3,H4,H5 is more likely than H6,S6,C6,D6 is simply the rules of the game. If a heart is led, it is mandatory to play a heart if possible, so most tricks contain four of the same suit, and a trick with one of each suit is extremely rare. When you add in the requirement for all four to be of the same rank, your second example is vanishingly improbable. This boils down to the fact that a card game is not a random selection of available cards (except when my partner is choosing an opening lead, of course).
Comment: There's also the game theory argument that people want to avoid hearts and will be playing their lowest to try and avoid the points, whereas in a situation where they can discard a card off suit, it's much more likely that they might try and discard an off-suite card of high rank. I wouldn't be surprised if all 10s or all Jacks came out in one trick, but other values seem much more unlikely.
Comment: Minor insight to improve this answer: there are 2 different factors here: A. As you stated, the rules makes the H6,S6,C6,D6 far less likely - even if we assume the players are just randomly play (legal) a card. B. The players aren't playing randomly - and while there's a solid benefit in not playing a high heart in a round opening with a low one, there's no benefit in playing the same number from a different suite. You mention both, but making it more explicit might make the answer clearer.
Answer: The chances of each player getting exactly one card of a set, be that set {2H, 3H, 4H, 5H} or {6D, 6C, 6H, 6S} is the same. However, 6 was just an example; the chance of each player having a card with the same value but a different suit is actually bigger then the lowest four Hearts being distributed like that. So the starting position is in favour of four cards of the same value being played.
But players don't choose cards at random. First of all, they have to follow suit if possible, so for none of the players to be able to follow suit would mean that it's later in the game and the suit has been exhausted, or that the opening player has all cards of that suit.
And that's just following the rules. But there's strategy and tactics to consider as well. Unless a player is trying to shoot the moon, they will typically play the lowest Hearts possible. So a player may play a 4H or 5H, hoping that one of the others will have to play a 6H or 7H at least. A player following suit with a 5H on a 4H may hope for the same. If the other players don't want the trick, the only thing they can do is follow with the 2H and the 3H, sticking the trick on the player with 5H.
There is no strategic or tactical advantage to following value instead of suit, so it really comes down to coincidence — although I can imagine players following value just for fun, after the first two cards have been played.

A Couple of Hearts Probabilities


Is there any way to limit bandwidth usage by process ID in Windows?

Question: Is there any way to basically do traffic shaping based on process ID or name within a Windows instance?
Answer: I use a great program called NetLimiter 2 Pro:
www.NetLimiter.com
It allows you to specify the exact maximum bandwith for applications AND processes, and it also runs as a service, so once set, you dont need the UI running.
Works fine with XP, Vista and 7 and does the job perfectly
(Infact, it's the only one i've found that works with the BBC iPlayer too!)
and at $30 for the full version after a 30 day trial, it's not much either!
Answer: Network bandwidth monitor shall be able to monitor real-time upload/download bandwidth and connections of every computer. So the administrator can diagnose bandwidth usage and network bottleneck. Some network monitoring programs, for example "WFilter Enterprise", can identify the connection protocol type of each connection, so you will be able to know what is running in your network.
Bandwidth monitor program shall also have a detailed bandwidth report.


EMT or PVC Conduit For Exterior Above Ground Electrical Run

Question: I'm installing a garage on the side of my house furthest from the electrical box. I don't want to trench the entire distance (60 ft), so I am planning on running conduit along the exterior of my home to the wall nearest the garage. From there I would dig my trench to run to the garage (~ 10 ft), and transition from an above ground to a below ground installation. I'm planning on a 60 Amp circuit to power the garage. EMT can be placed underground according to 358.10.A.1. If I read correctly it only needs to be buried 6 inches, where I need to go 18 with PVC. Am I understanding this correctly or off base in my analysis? What would be the recommended choice in this instance.
Comment: Rigid can go 6 inches deep.   EMT requires same as PVC though I would expect it to rust quickly.   Rigid is expensive, though that may not be such a big deal for you given the short run.
Comment: If you install PVC above grade, make sure you use at least one thermal expansion coupling, and use PVC clamps that screw down on both sides of the clamp and do not hold the pipe tightly, so that the clamps won't bind and the pipe can move. If you don't, you will end up with warped or broken conduit when the weather (temperature) changes.
Comment: If I ran PVC along the house, can I connect it to Rigid prior to the in-ground installation?
Comment: sure. Definitely at a junction box or conduit body, which I recommend you have as often as feasible for easy pulling.
Comment: Thanks for the response. After I posted this, I thought I just might go with Sched 80 and dig 18 inches to save a few bucks. I guess time will tell.
Comment: @FlyFish rigid is expensive if you have to go 300'.   If you are going 10', it's still expensive, but it's only 10' of expensive.  Yours is pretty much the ideal use-case for rigid,  because it's so short the costs won't get ouchy.
Comment: @Harper I agree with you but most DIY folks don't have threaders and benders like we do that's why I suggest PVC. Factory 90' S and nipples start making it "ouchy" for pipe.
Comment: @EdBeal I have local shop with a sign "we cut and thread pipe and shoplifters".  I usually just make sure about my lengths and go take the pipe to them.  For a simple U shape, OP should only have one critical length cut, and may be able to pre-ordain that with good design.
Answer: There are a few things you need to consider before running a long feeder and it seems you have at least given it some thought about method and materials.
First you say:

I am planning on running conduit along the exterior of my home to the
  wall nearest the garage.

The word "to" bothers me. Shouldn't it be "on". In other words you can't just run conduit on the ground. Conduit has to meet code requirements on securing conduit to something that doesn't move. So it needs to be strapped onto something so it doesn't move freely. There are different strapping requirements for each type of conduit and these can be found in individual articles in Chapter 3 of the NEC.
Also NEC code only allows 360 degrees of bends before adding a pull box this can be a variety of different types of boxes, condulets, etc. You will find you will need to follow these rules when you are trying to pull conductors as a 90 requires around 10 time more resistance than a straight pull.
You can bury EMT but most contractors I know won't do it. Depending on the PH of your soil could cause the conduit to erode, sometime in less than a year. PVC is you best bet. Also most good contractors will always bury conduit at least 18" in the ground if possible. The reasoning being that anyone accidentally cutting a 60A underground circuit is not an experience anyone enjoys.
Good luck on your project and stay safe.
Comment: I am planning on attaching the conduit along my house sides until it reaches the wall closest to the garage. At each corner of the house I will have a pull box. There will be 90 degree heading to the underground PVC, a 90 degree at the horizontal underground transition and another where I transition up along the garage. I'll have another pull box to feed into the garage. I plan on burying the conduit 18 inches. I'm still debating whether to use Schedule 80 or go down to 40.
Answer: If you do use EMT outside or in ground you will need to use compression couplings listed for wet/ damp locations, it will need to be secured every 10' and within 3' of the boxes. EMT would require 18" burial depth. Knowing you are going from 1 end of the home down then back up you will have more than 360 degrees of bends so conduit bodies or boxes will be needed to provide pull points. I will usually use conduit bodies to go around corners makes a tight turn with a LB then further away I will use another to make the turn to go in the ground LR or LL with 90 deg sweeps in the bottom of the trench at both ends and a LB or box to enter the building (box being a exterior disconnect). I think you might find schedule 80 PVC a bit cheaper and easier to work with than 1" or greater EMT.
Comment: I've abandoned the thought of using EMT for all of the reasons everyone has mentioned.


The effect of the boundary condition on the convergence of the fdm scheme

Question: I know the boundary condition is usually a tricky question. However, I am testing a finite-difference scheme for the equation of the form $$u_t=a(x)u_{xx}$$ that I know the analytical solution of. So if I specify the Dirichlet boundary condition, I can see the perfect convergence with a desired rate, but if I specify the value of the derivative I see the deterioration of accuracy of the numerical solution at the boundary(still have a good convergence in the middle of the grid). Both are exact from the analytical solution but looks like the derivative is not a good choice. What I think is that there should be only one solution that satisfies the initial condition and such a value of the "slope", or I am wrong? I might have a bug in my code but could not spot it so I wonder if imposing the partial derivative on the boundary instead of the value of the function could destroy uniqueness and this is why I am converging to a slightly different solution?
Comment: It sounds like you might have a problem with the order of approximation of your neumann (derivative) boundary condition.  If you're using a centered difference scheme for $u_{xx}$, then you're tempted to expect your method to be $O(\Delta x^2)$.  But if your boundary condition is implemented with a forward or backward difference (i.e. $O(\Delta x)$ accuracy), then the whole scheme will only be $O(\Delta x)$ in space.
Comment: Are you using neumann boundary conditions on all boundaries?  If so, then you have an ill-posed problem with infinitely many solutions.
Comment: What do you mean "both are exact from the analytical solution"? If both methods give correct results, what's your problem?
Comment: I agree with @Paul that you might not discretize your Neumann boundary conditions correctly.  You could use the ghost points outside the domain to obtain second-order convergence.
Comment: @Dan: that means I can compute the value of $u_x$ and $u$ on the boundaries exactly and set it to those values, but I do find numerically the value inside of the domain. What I see that if I plot the error it has significantly larger value close to the boundaries if I set the derivative instead of the function.
Comment: @Paul: No, I am using one sided approximation but using values at three points $u_0,u_1,u_2$ and $u_M,u_{M-1},u_{M-2}$, so that I end up with second order. I set the boundary condition on both sides of the interval $[x_{min},x_{max}]$. Assume $a(x)>C>0$ so that I do have to impose boundary conditions on both ends.
Answer: As Hui pointed out above, to apply Neumann boundary conditions correctly you should utilize ghost points and extend your $n^{th}$ order discretisation stencil to your domain boundaries. Utilising forward/backward difference or extrapolation at the boundary will degrade your solution.
Assuming a $2^{nd}$ order central difference scheme the Neuman boundary condition, $u_x(t,x=0) = p_0(t)$, becomes (omitting $(t)$'s for convenience):
$$
u_x\rvert_0 = p_0 \approx \frac{u_1 - u_{-1}}{2h}
$$
$$
\Rightarrow u_{-1} = u_1 - 2hp_0
$$
Now, substitute for $u_{-1}$ into your discretised equation at the boundary, to obtain a Dirichelt BC $u_0$:
$$
u_0(t) = a(0)\frac{u_1 - 2u_0 + u_{-1}}{h^2}
$$
$$
\Rightarrow u_0 = a(0)\frac{2u_1 - 2hp_0}{h^2 + 2a(0)}
$$
Applying the Neumann boundary condition in this way is consistent and is strictly equivalent to applying the analytic Dirichelt bc in the limit $h\rightarrow 0$.
As for which is more accurate, for finite $h$, if you apply the Dirchlet condition at the boundary you impose exact agreement between the analytic and numerical solution at the boundary, but your estimation of the solutions derivative at this point will contain a $2^{nd}$ order error. Applying the Neumann boundary condition simply does the reverse, i.e. yields exact agreement between the analytic and numerical values of the derivative of your solution (estimated using your finite difference stencil) at the boundary, while estimations of $u$ at this point will contain a $2^{nd}$ order error. In the limit $h \rightarrow 0$ both methods should converge to the same unique solution.
If you are not utilising ghost points then you are not applying the Neumann conditions in a consistent way and your result will indeed simply be less accurate then when you solve using the Dirichelt boundary conditions.
Comment: I agree with you that I must have a bug in the code as both approximations should be consistent. However, I see no problem approximating the derivative from one side by setting $u_x(0)=-3/(2h)u_0+2/hu_1-1/(2h)u_2=const$ and then getting $u_0$ from there. This approximation is of second order and no need for the ghost point!
Comment: I know this approach well, having used it myself many times. This is indeed 2nd order but personally I have found it frequently detrimental when used in stiff time evolving systems and I've never seen it recommended in a text, though I do not have a rigorous argument as to why. Perhaps a good follow up question!
Comment: Actually,if you approximate the derivative with a second order accuracy, then $u_x(0)=O(h^2)$ the value itself would be approximates as $u(0)=$


Which Confederate State provided the most troops in the American Civil War?

Question: Of all the states that elected to secede during the American Civil War, which one had the largest number of citizens who actually fought for the Confederacy? I would also be interested if anyone could find which state had the largest number of casualties.
Comment: If you are going to give a posting a downvote, at least have the decency to explain why!
Comment: Just for clarification are you referring to whites or would you also include slaves forced to fight for the Confederacy in any respect?
Comment: Gosh, this is a tricky one to answer. I spent a bit of time researching it, but couldn't find any sort of break-down by state. And indeed, it does help a bit to discount blacks, who were enlisted into a separate blacks-only army. (There was incidentally a very good film made about this, whose name I forget.)
Comment: I believe you are thinking about Glory with Denzel Washington. That was about an all black unit that fought for the North. Excellent movie!
Comment: Interesting twist, that. I had meant just whites, mainly because I hadn't considered that there were any slaves who were forced to fight. I'm not sure any source would have kept records on them.
Comment: Probably not many records but I know they took part in grunt work, not much in the way of fighting since giving them weapons really would have done John Brown proud.  I was just curious as to how you were defining troops in this respect.
Comment: @StevenDrennon The Confederate states for sure wouldn't have any black units, as it was only an opinion brought to the table in 1865 right before they surrendered.
Comment: There is an incomplete list of the Confederate Armies here: http://en.wikipedia.org/wiki/Confederate_States_Army
Comment: @Steven Drennon: It was indeed! And yeah, they fought for the Union... I suppose it was rather more common than blacks in the Confederate army. Thanks for the reminder. :-)
Comment: I would sure like to see the entire table the 1912 The numerical strength of the Confederate Army. I think it wouls show that a much greater number came from the state
of Missouri than is commonly known today.
Answer: As far as Union states go, this table seems to provide accurate information. However, the info on Confederate army is very incomplete. You can find statements that North Carolina supplied the most soldiers (125,000) to the Confederate army all over the Internet. The original source seems to be a speech from 1904 by Hon. Theodore F. Davidson in Raleigh:

She [North Carolina] was next to the last state to secede from the
  Union, and in February, 1861 she voted against secession by 30,000
  majority; yet, with a military population of 115,365, the State of
  North Carolina furnished to the Confederate army 125,000 men. . .Of
  the ten regiments on either side which sustained the heaviest loss in
  any one engagement during the war, Georgia, Alabama, Tennessee,
  Illinois, New York, Pennsylvania and New Jersey furnished one each,
  and North Carolina furnished three. North Carolina furnished from
  first to last one fifth of the entire Confederate army, and at the
  surrender at Appomattox, one-half of the muskets stacked were from
  North Carolina.

Given the nature of this speech, it is probably not the most reliable source of information - and it doesn't actually claim directly that North Carolina supplied more soldiers than any other state. In fact, if you search hard enough you will also find statements about Tennessee and Texas as the states that contributed the most soldiers to the Confederate army (not backed by numbers). For comparison one would need to at least look at the number of soldiers supplied by Virginia but that number is very hard to find.
I finally found the book The numerical strength of the Confederate army from 1912 which lists the stated numbers of enrollment into the Confederate army:

Virginia: 175,000
Florida: 15,000
Georgia: 120,000
North Carolina: 129,000
South Carolina: 75,000
Mississippi: 70,000
Alabama: 90,000
Tennessee: 115,000

The book goes on to compare these numbers with the actual population and comes to the following conclusion:

In the light of the facts just stated we must conclude that the
  Southern writers quoted by General Adams have, in their zeal for the
  honor and glory of their several States, greatly overestimated the
  number of men contributed by the same to the Confederate armies. This
  would be more probable a priori, than that the leading men in the
  Confederate army and Government who were at the sources of
  information, and who ought to have been well informed, should have so
  enormously underestimated the strength of the armies of the South; but
  the tests to which we have now submitted the figures given by these
  State historians demonstrate their error beyond the possibility of
  doubt. They must be cut down by several hundred thousand. A large
  element of this error is to be found, as I have suggested, in the
  failure to observe the great number of re-enlistments that undoubtedly
  took place, especially in 1862, when the terms of service of nearly
  all the Confederate regiments expired.[Pg 61] This duplication, in the
  opinion of the military Secretary of the United States, reduces the
  total by twenty per cent.

For us this means: If you look at the "official" numbers then the state that supplied the most soldiers was Virginia. The sources claiming otherwise apparently took the statement "North Carolina supplied many soldiers" and turned it into a superlative. As to the real numbers: I'm not sure whether they are known by now, I couldn't find anything resembling a reliable source.
Comment: @StevenDrennon: IMHO, while you can sympathise with another answer, it is in the interest of future users to just accept the more correct answer.
Comment: I believe you can change answers to make them more appropriate if you get a better one after a period of time.
Comment: I awarded Tom with the answer because he was the only one who had answered for some time. However, I chose to award a 50 point bounty to this answer because it was more complete. Thanks for the effort!
Answer: Just to back up Wladimir's post of the inaccuracy of the numbers.
Josh Howard a North Carolina Historian stated in this article

"The time has come to get it right," said Josh Howard, a research historian with the Office of Archives and History in Raleigh. "Nobody has gone through man by man looking for the deaths."

North Carolina is only believed to have sacrificed the most men to the war. The article linked above is from 2010 where he set out to figure out if this was true or not. However as of now he has completed a study that attempts to put the myth to rest.
Additional Info:
Josh Howard's Study Page (No results listed)
After a year+ of work it looks like he came to a conclusion. He states that the North Carolina death toll would be closer to 32000-35000. Also when taking into account the inaccuracy of other military records from other states it looks like North Carolina still comes out on top.
From this article

In all likelihood, North Carolina still ranks first in fallen Confederates. If records in Raleigh are wrong, it's a good bet the rest of the Southern states have inaccurate counts, too. Second-place Virginia, also reviewing its count, is moving much closer to North Carolina in the number of dead.

He also concludes that:

But both Howard and Purser admit the numbers will never be 100 percent accurate.

Extra Interesting Info:
He did debunk the myth that the first casuality for the south was that of soldier from North Carolina.

A Virginia captain beat Pvt. Henry Lawson Wyatt, a 19-year-old from Tarboro, to the grave by nine days;
Answer: One would think that the answer was Virginia (the most populous Confederate state), but the answer apparently was North Carolina on both counts (contribution and casualties).
http://answers.yahoo.com/question/index?qid=20090929211811AA1fKYQ
Comment: Yahoo Answers is not exactly a reliable source.
Answer: "Which Confederate state supplied the most troops" and "fought for the Confederacy" are slightly different questions. Tennessee actually supplied the second largest total of troops--more than North Carolina--from any Confederate state. But more than 30,000 of those fought on the Union side. (And not including 20,000 African-Americans.)
An issue which may be particular to East Tennessee is that many men served both sides. In my research on Hawkins County, Tennessee, I have so far found that nearly 8% of the men who served in Confederate regiments at first later served in Union regiments. While a few joined US Volunteer regiments for frontier duty, most deserted their Confederate TN regiment and enlisted in a Union TN regiment.
Comment: East Tennessee was full of Northern loyalists, and unlike West Virginia help could not get to them for some time.  Adding West Virginia's union totals would probably put VA back on top.
Answer: Virginia acknowledges in its records that it provided over 155,000 troops for confederate armies while North Carolina acknowledges over 133,000.
Interestingly, Virginia also provided over 32,000 soldiers for the northern armies, among them General George Thomas.
Answer: Battle of Gettysburg saw new York regiments as most plentiful on union side.virginia regiments most plentiful on confederate side.there is your answer simple Virginia.
Comment: This would be improved with a) some references and b) some indication of why you consider the Battle of Gettysburg is representative of the entire civil war, in regard of which states provided troops.


How can I (painlessly) add or remove keys to my key ring?

Question: One of the most excruciating things I have to do is to add or remove some keys from a key ring.  I have to dig my way into the crack of the ring with my nails, which really hurts.  What else can I do to save myself from the pain?
Answer: I have generally used two methods for removing keys from keychains:
Staple-Remover Method
Since staple removers have sharp, thin teeth, simply place the sharp points between the keychain rings and slowly press down. This should spread the keychain apart and make it easy to roll the new key on/take the old key off the chain.

Coin Method
Since I often don't have a staple remover readily on-hand, I usually use a coin. This video and description are helpful:

Get a coin about the size of a quarter.
Press the edge of the coin against the key ring at a 45 degree angle, near where it opens; the coin will slide under part of the key
  ring, lifting the end up.
Apply pressure to the coin so that it lifts up the end of the key ring enough to slide the key on. Then slide the key on.
Remove the coin and slide the key on the rest of the way.
Comment: There are special tools that do the same as the staple remover, I bought mine in a beads shop, but the staple remover is around in many houses and offices. +1
Answer: I end up using the key I want to put on the keyring.
I slide the cuts of the key into the groove, opening it. Then, I keep pushing until the entire blade is in the keyring. I then rotate the key until the hole is relatively near the start of the keychain. I slide it on, and done.
Answer: I usually use a staple remover to open a crack in the ring and then add or remove the key painlessly.
The smaller the staple remover, the better, because a bigger one might not fit or damage the ring.
Comment: @JemEripol [Answering your own questions is encouraged](https://stackoverflow.blog/2011/07/01/its-ok-to-ask-and-answer-your-own-questions/)
Comment: why would you answer your own question?
Answer: If you carry a small pocketknife, like me, you can use that to slip into the crack, and pry open. Stick your key into the crack, from either side, remove the blade, and slide the key in/out of the ring. This is convenient for me, because I carry both my pocketknife and my keys in my pockets, so they are with me all the time.
Warning: Blades are often sharp. Use common sense and try not to cut yourself.
Comment: @cullub *knives. I added that because of how many people end to be careless with blades.
Comment: haha sorry spelling error.  Yeah, "use common sense".
Comment: Even with care, this is one of those situations where I'd definitely cut myself eventually. Accidents happen and blades slip; common sense is not always enough.
Comment: @DangerZone Haha! Ok then. Nut I do it regularly and have never cut myself. I find that blades don't slip if you know what you're doing. ;D
Answer: Rather than fighting the problems of the typical key ring, you may want to consider a different design. Here is a review that covers about two dozen ideas about ways to hold your keys:
http://www.carryology.com/utility/guide-to-carrying-keys/
The FreeKey is made of flat metal shaped into a ring, but the loops pop apart when you squeeze it. It seems like the most direct replacement that would solve your problem.

Another idea I've seen is an incomplete ring with "end stoppers". There's a round bar bent into a "U" shape with balls on each end to keep the keys from sliding off. One of the balls can be screwed off in order to add or remove keys.
Here is one example of such a horseshoe keyring:
https://www.amazon.com/Jzcky-Shzrp-Keychain-Horseshoe-Keyholder/dp/B077GX2XS3/

I don't have personal experience with any of these. I just found them by searching online.
Answer: As a preventative measure, I keep a small carabiner on my main key ring, and attach peripheral keychains to the carabiner instead of the ring when I need them. It reduces the number of times I have to fiddle with key rings and lets me travel with fewer keys - for example, if I'm biking to school then I will take the car keys off the carabiner and leave them at home.
For the times when you do have to remove keys from the ring, JSW189's staple-remover method looks promising.
Answer: The 'non life hack' method:
Get split ring opening pliers (an image search will show many, but here is one from a commercial site.)
Till I bought that item, and still when it is home while I am elsewhere, I used to use the file on my small pocket knive. Or the file I keep in the bedroom.
Insert the tip, turn sideways and you have enough of an opening to get a small key in.
Answer: I agree these hard keyrings are incredibly annoying.
Please try to not use your nail, you are too likely to break it.
Here are the solutions that come to mind:

Use a knife (not one with a cheap blade, you certainly don't want to break it). Though, it still requires some practice to get the right gesture. And you are guaranteed to damage the blade edge.
Find a lighter keyring. Sorry no photo for now, but you can find "cheap" keyrings that are made of a much thinner wire. They perfectly do the job and are suuuuch a pleasure to manipulate.

Or, you can always carry a staple remover.
Answer: If you have one of those nail files with a point on the end, you can use that to add and remove keys.
Comment: I think a picture here would greatly improve the quality of this answer.


What are the pros and cons of having fewer, smaller projects compared to larger, bigger projects?

Question: With all other things being equal, let's say you could pursue getting 6 clients that would pay you $5,000 per contract, or getting 3 clients that pay you $10,000 per contract. Assume that the work for option A and option B are equal. Would you prefer one approach to the other? What are some things to consider?
Comment: The size of the client isn't the point in this case as much as the size of the project. You might consider editing your question to reflect this.
Comment: @AvonelleLovhaug good point. Question updated.
Answer: Note that there is a distinction between "project" and "client". Large clients can have small projects and vice versa.
More/Smaller Clients:
Pros include:

you are diversified and therefore, the loss of one client will have less impact on your work/cash flow
getting into more clients should increase your marketability because of your greater visibility and larger number of reference clients and projects
broader experience & background because you are involved in more and different projects and clients.

Cons include:

more small projects leads to more (unpaid) overhead (there's always a certain amount admin work such as setting up contracts, time-keeping, and billing required for each client)
greater amount of task-switching overhead and therefore more potential for lost time
greater possibility of conflicts as now you have more calendars to juggle
potentially less follow-on work as smaller clients have smaller budgets / capacity for work.

Fewer/larger clients: Flip the above, plus add the Pro that larger clients offer potentially greater opportunity for finding additional projects within the same client.
For your specific question, I would prefer 3 x $10,000. Your project portfolio is still diversified and your project management / administration overhead is reduced. And either of the two options you mentioned is MUCH better, IMO, than a single $60,000 project. Large projects are nice for cash flow, but you can get buried in the project and lose your marketing edge... remember the old consultant's dilemma: "If you're billing, you're not selling; and if you're selling, you're not billing!" Striking the right balance is important for long-term success.
FYI, I've been an independent consultant since 1979.
Answer: I like working on a mix of larger and smaller projects to even out work flow and cash flow.
Sometimes, you may be waiting on clients for a decision or other reasons and it's good to have something else to be going on with. A mix of projects means you will always have something to be going on with.
Taking on too many large projects can mean waiting a while to get paid. A few smaller jobs happening at the same time can bring in some cash in the meantime.
While larger projects may have lower overheads (less invoices etc), advantages of smaller projects might include:

opportunities to network with more people
add more jobs / industry sectors etc to your portfolio
smaller jobs can often lead to larger jobs
less risk (e.g. if job goes bad or clients do not pay)
learn new skills gradually rather than in big chunks
Answer: I think it really depends upon your work style and, to a degree, the type of work you do.
I prefer to mix thing up and have both going at most times. I enjoy the fact that if I'm in the middle of a large project I can take a break, do something small and alter my mindset for a period of time. This generally results in "fresh eyes" on larger projects and allows the work to be better overall. I'm simply not the type of person that can spend all day every day working on the same thing. I need variety to keep my interest going and ultimately to solve some design issues which may occur on projects. I'm a multi-tasker at heart, always have been. I know that about myself and try and steer my work schedule to accommodate that aspect of my personality. I get very, very, bored if I only have one or two large projects to complete.
As for pros and cons of each one that depends on the source of projects.
I generally only work with a few clients who have been regulars for years. It's not a problem to invoice these clients regularly regardless of the number or size of projects they've given me. However, if I were doing a great many small projects for a great many different clients, I would not enjoy the additional clerical time it would require to invoice for each and every project. At some point there would be a critical mass where I was spending so much time on clerical details that profit would most likely suffer, not to mention my overall enjoyment of freelancing. I don't want to be an accountant or office manager. I do it because I must. :)
As others have mentioned, the big projects can at times be an issue if you can't invoice for them regularly. It's difficult to go long periods of time without any income or any income of note if working on a large project. For this reason I explain to the client (and in contracts) that invoicing will occur at milestones. This allows me to avoid that feeling of working for nothing, even though it's not really the case. No matter how much you are working, it's important to see a check every now and then. For me it's not about concern the client won't pay, of course they will if I invoice when the project is complete. I simply need to see checks every now and then so I feel like I'm doing well and not spinning my wheels without getting ahead.
In your specific scenario -- 6 or 3 jobs.. my choice would depend entirely on the actual projects, not on the return, since the return is the same. I may even pick some from A and some from B (which may result in more return).


Would it be ethical to use AI to determine a user's gender from the content they upload, without them knowing?

Question: I've been thinking about this for a few days and can't tell if this would feel morally just to an average user
Comment: Interesting question but I think it's in the realm of business ethics or philosophy as opposed to UX. AI tools analyze text and actions which are, for the most part, outside the realm of UX.
Answer: Ethics aside, I think this could potentially create a number of different issues. What if your algorithm guesses wrong and I'm stuck with a UI that's targeting incorrectly? What if my wife and I share an account? What if I'm a (insert orientation here) (insert gender here) who [coaches, supports] a [men's, women's] [volleyball, football] team? People are very diverse, and you could make many mistakes. Would you then provide tools for the user to correct these mistakes? How would you be able to do so without the user being offended?
Instead, I see many fewer issues that might arise from a section like the following:

Let's get to know each other!
If you'd like, we can help tune your profile to match your interests.
You can start by selecting some of your interests from the list below, or try searching for your own.
Fishing Cooking Soccer Video Gaming Social Media
Search for my interest...
Skip this section →

You could continue with other questions that might actually be relevant to your shaping your UI or application, allowing the user to omit/delete details for any or all questions.
Being purely an opt-in experience prevents any issues with the user feeling like your app may be "talking about them" behind their back.
In this case, specifically at this point in time, I think it's wise to be transparent about what data your application knows (or thinks it knows) about your users.
Comment: My reasoning is: if any person can look at another person's public profile and visually determine their gender without even consciously trying to, what makes it morally questionable to write code to do this same, extremely evolutionarily fundamental activity. You don't give consent to strangers in public to determine your gender without you knowing. It's so intrinsic to human behavior that it's expected.
Comment: Your suggestion exists at the intersection of many controversial topics. Gender, user privacy, AI, and data collection are all regularly in the news, with people voicing loud opinions on either side of each topic. By not allowing the user any control, you're imposing your view of all 4 topics on the user secretly and involuntarily. In order to avoid the possible legal implications that should be accounted for and maintain the user trust that could be lost from incorrect conclusions, I'm offering a suggestion of transparency by allowing a user to opt in to this feature instead.
Answer: Aren't we already doing things with technology that are not ethical? But to answer your question, yes, it will be unethical to use gender to target a user. It will mean that the AI will be fed a list of things to look for for a certain gender which is again gender-bias. I find targetting users unethical but using gender basis would really be something else. I am not sure if I am on the right track but ads are run keeping in mind the target audience which involves the age, gender, etc. That is done by humans but still.
Answer: The general principle is that data belongs to the person who generated it, and permission should be sought before you use someone else's possessions.
So, it is ethical to use it to infer whatever you like about a person, provided that you ask permission first.

Would it be ethical to use AI to determine a user’s gender from the content they upload, without them knowing?


InstallScript String replace fails in windows server 2008

Question: I am now facing a problem with the installer that i have created with InstallSheild 2009.
There are some configuration files which need the installation path of the application.
and this is done by the installer through an installscript.
On building the installer we uses a template '<Base Path>' and at the end of installation the install script replaces the string with the install location. (say C:\Program files\)
This is made for windows servers. and it is working fine in windows server 2003.
And it works in Windows server 2008 if the User is ADMINISTRATOR.
Other wise it fails to replace the strings even thought the installed user has full previlege.
Anyone having any idea regarding this please help me....
Answer: The issue has been solved when I just right click and selected 'Run as Administrator'


Why are berries so expensive?

Question: I am trying to eat healthier with less processed foods and I'm a pretty smart guy to begin with. But I can't figure this out for the life of me - why are berries so expensive? I love things like boysenberries and blueberries but I almost choke when I see their price in the store. Why are berries expensive?
Comment: While I agree that "expensive" is open to interpretation, I don't think that most would disagree that berries generally cost more than say apples or bananas or oranges. I believe that there is certainly a place for fact-based answers that are not subjective... as the answers we have show. I don't believe there is a reason to close this as "primarily opinion based".
Comment: At this time of year, most berries are flown in from South America, as it's the wrong time of year to grow things outside in the northern hemisphere.  Although a lot of produce is grown in California due to its longer growing season, there are still times of the year when even they can't produce vast quantities (and greenhouses increase the costs)
Comment: @Catija, a botanical "berry" has nothing to do with a culinary "berry".
Comment: @Joe but that's exactly the point... And, I suppose if you want to get technical, a banana **is** a berry... While (botanically speaking) strawberries and raspberries are not.
Comment: related : http://cooking.stackexchange.com/q/65871/67  (regarding the costs in growing & picking grapes)
Comment: 40 cents for a pound of bananas vs $3 for a 6 oz container of berries. ($8/lb). Crazy, I agree.
Comment: @JoeTaxpayer : unfair comparison -- bananas can be shipped green (less damage / loss in shipping, can be shipped through slower means). And they aren't nearly so labor intensive to pick.
Comment: the Joe that mentioned the botanical vs. culinary 'berry' is not the same Joe that mentioned foreign produce & shipping.
Comment: Nitpick - do you want foods that have had less processing (but some is still okay), or fewer total processed foods?  The word changes the meaning, hence asking.
Comment: As several answers have shown, it is a combination of things. This is reflected in the cost of frozen berries, which are still not cheap, but a lot more affordable. Frozen berries do not have the shipping and storage problem as fresh ones do, but only the picking cost, which is still a bit higher than other fruits, it seems.
Answer: It is a combination of many factors. To sell you one perfect apple, one perfect bunch of bananas, or one perfect half-pint of berries requires:

the land to grow on
workers to plant, tend, weed, and pick
transportation to market
loss allowance for fruit that's bruised or spoils in transit
loss allowance for fruit that spoils while at the store and people won't buy it

Many of these factors are objectively higher for berries than for applies or bananas, especially given their short shelf life and tendency to bruise.
This puts a floor on the price growers and stores can charge. Then on top of that, they are delicious and healthy, so at least some people will pay that price. This removes downward pressure to sell them at a loss to get you in the store.
A better question is what can you do about it? The answer is generally to use frozen berries (they don't incur the spoiling and bruising losses) or to eat berries only when they're in season locally and eat other kinds of fruit the rest of the year.
Comment: Another option worth mentioning is going to a local farm and picking yourself. Around here we can pick for around 20% of the supermarket sale price
Comment: @casey Sure, that probably saves a little money but even saving 80% of a few dollars is a small saving compared to the investment of time.
Comment: Blueberry bushes grow well in pots, so they're ideal fruit to grow even with next to no outdoor space. The season can be a few months with a mixture of varieties and they grow in a wide range of climates.
Comment: @casey That's provided you have a local farm growing them. We don't. We have greenhouses, but they usually don't allow visitors picking them.
Answer: There's a variety of reasons I can imagine:

They're more delicate than most other fruits, so shipping without damaging is harder. Loss due to crushing is expected.
They go bad quickly, which can limit the area they can be delivered to and the method of delivery (planes are more expensive than trucks) but also gives them significantly shorter shelf life in the stores - meaning stores have to charge extra for what they sell because they have to discard anything that starts to rot.
They're more difficult to pick because they're tiny and (often) protected by thorns, so the cost to produce is higher.
They're in additional packaging... apples are loose in giant boxes, berries are usually in small plastic containers that add cost to the overhead.
Answer: Think of it the other way around. I got the answer by asking why are bananas so cheap. I live in Michigan, and bananas, even though they have to be shipped from points far south of here, are cheaper than non-cull apples which can be grown locally. The reason (if you remember the Banana Boat Song by Harry Belafonte) is that bananas grow in 6, 7, and 8 foot bunches, meaning that they can be harvested very quickly without a lot of labor. Apples have to be picked one at a time. You will also notice that strawberries are cheaper than any other kind of berry. This is because they are bigger, and therefore take less labor to pick the same quantity. Potatoes and wheat are harvested by machine and therefore cost even less
Comment: Referencing facts would vastly improve your answer (or other experts). Berries are expensive due to a number of factors, including cost of production, cost of transport, and short lifetime and season.
Answer: Another answer perhaps overlooked is that they are smaller than fruit Irregardless of cost of production, shipping and storing, a small box of berries with 30 berries in it seems like more value than an single apple, even though they have the same weight.
Likewise, the way they are used affects how much people will pay; They are often used more as garnish and decoration. A small box of raspberries can be enough to spruce up a dessert, whereas fruit often needs to be a bigger ingredient.
Comment: Can you support the use statement with facts? People regularly make smoothies with berries, if not entire desserts like cobblers and pie.  I'd argue that the reason you often find berries only used as garnish is **because** they are expensive, not the other way around.
Answer: I think berries are getting more and more expensive because it takes tons of water to grow berries and slowly we are losing water on this planet so it costs more to water them. also if you are buying organic ones from a local farmer that is amazing but is probably more expensive because its organic so they rot faster because there is no pesticides witch is great! i do know that it is possible to buy cheap healthy food you just have to do a little researching at stores near you and maybe if you are up for it you could start a little garden in your yard.
Comment: Lack of pesticides causes them to rot faster?  I could see losing a higher percentage to diseases, maybe less production due to different fertilizers or alternate varietals, and higher labor costs for increased monitoring ... but rot 'faster' seems strange.

Why are berries so expensive?


Will we lose our reputation we earn from hats when we lose them?

Question: I got the hat "retro fan" and I got 2 reputation points. Once the hats are gone, do we lose the amount of reputation we get from them or do we keep it?
For example, if I got the hat X and get Y reputation points, once it reaches January 4th, will I keep my reputation or lose Y reputation points? Sorry if this is a really bad question!
Comment: Ironically you lost reputation by asking this question. The answer could have been supplied in a comment and your question closed or deleted. The Winter Bash feature is not new and users know that rep is earned by upvotes and whenever they accept an answer, etc. It's common knowledge, hence the 7 downvotes on your question (also 4 upvotes) and the gratuitous upvotes on the very easy, albeit perfectly correct, answers.
Comment: @MonicaCellio I'm actually berating more the downvoters than anything else. Maybe my comment helped stem the flow?
Comment: @Mari-LouA a quick look at Cursor's network profile shows that this user is not experienced with the network.  Let's not berate a new user for not knowing "common knowledge".
Answer: Hats neither give reputation nor take it away.  The 2 rep that you got is not connected to hats.  Perhaps you accepted an answer, had an edit approved, or downvoted two answers that were later deleted.
Answer: Your points are not from the hats, it's from something unrelated to Winter Bash, so simply at the end of Winter Bash, you'll still have the rep.
Answer: I realize that there are already four answers all saying basically the same thing, so a fifth answer would be kind of redundant. However, there is an important point that none of the other answers addressed. It is true that no reputation is awarded for hats; but we can go further than that. We can actually see what you got reputation for.
First we have to figure out which site you earned the reputation on. Here is a screenshot of the Accounts page in your Network Profile:

Right away we can see that you have only ever earned reputation on two sites  — Stack Overflow and Meta Stack Exchange — so we won't have to do that much digging. Let's start with your Stack Overflow account.
If you go to the Activity page in your account and look through the tabs there, one of them is called "reputation". This tab contains a record of all the reputation you have earned on Stack Overflow, with the more recent earnings at the top. Here is a screenshot of what we find:

A quick glance is enough to tell us that you haven't earned any reputation on Stack Overflow since November 28th. Clearly the reputation that you think came from a hat cannot have been awarded on Stack Overflow, as Winter Bash had not even started at the time of your last reputation awarding.
This leaves us with your Meta Stack Exchange Account. Following the same procedure, we get this screenshot:

As we can see, all your reputation has been earned today or yesterday, and it all comes from two posts. Yesterday you earned 15 reputation (three upvotes of five reputation each) for your question about the leaderboard. Besides for that you had no reputation changes prior to posting this very question. Thus, there does not appear to be any instance of you getting a +2 reputation prior to asking this question about the +2 reputation that you got.
Now it is a little harder to track the reputation notifications that you might have received after posting this question, because you got some negative reputation. Negative reputation does not generate a notification when it is earned; instead it is held until you earn positive reputation exceeding the negative reputation and then you get the notification showing you the difference between the positive and negative reputation.
In this case you started off with three downvotes, for -6 reputation. You would not have received a reputation notification at that point. Then you got an upvote for +5 reputation, but you would still not have received a notification since the negative reputation still exceeded the positive reputation. Then you got three more downvotes for -6 reputation, which would have you at -7 reputation needing to be applied. Then you got two upvotes for 10 reputation, so you should have gotten a notification of +3 reputation (10-7=3). Then you got another downvote and another upvote, which would give you another notification of +3 reputation (5-2=3).
Based on the above, it would seem that you did not receive any +2 reputation at all during Winter Bash. The only reputation that you earned during Winter Bash prior to posting this question about whether you would lose your hat-generated reputation was the +15 that you got for your earlier question about the leaderboard.
If you want to try to figure out precisely which reputation gain was the one that you associated with getting the hat, you would have to figure out when you got the hat. First we have to check which site you earned the hat on. A perusal of your profile page shows that you earned it on Stack Overflow:

Knowing this it should be pretty simple to figure out when you got the hat — the hat you got is for voting on a post over a year old. You can check your voting history by  going back to your Activity page and clicking on the last tab "votes". This tab is only visible to you so I can't provide screenshots, but once you go to that tab, you will find a bunch of sub-tabs, the second of which is "upvotes". By clicking there you will find a list of the posts you have upvoted. All you have to do is find the post that was over a year old (or if there is more than one such post, then the first one from after Winter Bash began). When you find the post you will see a number of days or a number of hours or a date listed to the left of it. If you hover your cursor over that number/date it will provide the exact timestamp of the vote. Once you have that information you can go back to the reputation tab in your Meta Stack Exchange Account and compare the timestamps there to see which reputation change occurred around the time that you cast the vote on the old post, and that will presumably be the reputation change that you thought was from  getting the hat.
Answer: Any votes you cast, comments you leave, ask questions, post answers, or any of the various other actions you can do on the network, and the reputation and badges earned via the same remain even after WB is over.
The triggers for the hats depend upon doing a specific task on the network, and that's where their relationship ends. The hats are related to the task you do on the SE network, not the other way around.
Answer: Winter Bash does not effect reputation in any way, unless you count earning reputation from posts that come from winter bash (show off your hats, knitting, etc). Because of that, you won't earn or lose any reputation at the end of winter bash.
Comment: How does this answer differ substantially from Monica's?
Comment: @Mari-LouA it adds some more information about indirect ways reputation can be earned. Similar answers, I admit, but not the same.
Comment: Where does it say how rep can be earned?**EDIT** Oh, you mean MSE posts but the OP received the Retro Fan "hat", you don't get it by posting anything, it is totally unrelated to rep.
Comment: @Mari-LouA "unless you count earning reputation from posts that come from winter bash (show off your hats, knitting, etc)."


How do I avoid leeches?

Question: The last time I was attacked by leeches I thought I'd taken enough precautions such as pulling my socks over my trousers and avoiding walking through particularly wet areas or long grass but I still got them sucking on my ankles. What are the best methods to prevent them finding you interesting in the first place? And what will stop them finding your skin if they do take an interest?
Comment: Where do you hike that is so infested?  I found these stylish Anti Leech Socks in a google search: http://www.mosquitohammock.com/AntiLeechSocks.html
Comment: Did the leeches go through your socks? Can you let me know? I thought pulling socks over would work
Comment: @Huangism Leeches can easily get through your socks.  They can also somehow get inside a hiking boot and down to your toes.
Comment: I am going to Lake Minnewaska for the 4th of July weekend and I heard that there are leeches in the lakes! I really want to swim though. I want to know what REALLY works.
Answer: I have lots of leeches in my (otherwise) lovely swimming hole which is in a creek just as it leaves a lake. I read up on possible leech deterrents and now I rub my  exposed skin with just about any kind of skin cream and they all seem to work. Waterproof sunblock is my current favorite but I've also used Off (Eucalytus) and even ordinary moisturizer. I haven't yet tried a cooking oil which might be better for the environment and I bet it would work. Coconut oil is a favorite but they might just like it!
I'm too lazy on a hot day to rub stuff  all over so I just do my feet and legs. The leeches don't seem to get inside a one piece bathing suit. I think they attack feet and legs because they are nearer the bottom of the lake but really don't know why my arms, shoulders, neck/head don't seem to interest them. I also hurry into deeper (about five feet) water and I think that helps. People who stand around in the shallows, especially near reeds, seem to attract some big ones.
Yesterday, my husband was fishing off a bridge in very shallow water while I swam and he got his hook caught so I bravely rescued it. Later, I had leeches (tiny ones) all over my rubber sandals but none on my feet. I was using waterproof sunblock and had already been in the water for about 20 minutes so the fact that the creme still worked was cheery.
I grew up in central Saskatchewan and leeches were just a fact of life. Any kid who wanted to go swimming just lived with the them. Now I am not so tolerant but I still love the water so I needed to find a solution when we bought a cottage in central BC.
Today, I tried something different. I put on a pair of tights and they worked perfectly, but since grey tights look seriously dorky, I'm going to try "nude" panty hose and no one will probably even notice. Not that there's anybody around except the occasional fisherman.
Answer:
You can spray your socks/shoes with some type of deet spray or some tobacco water (soak some tobacco leaves in water).
I've heard that salt affects leeches similarly is it does slugs, so you could carry some of that with you and rub some on your legs/feet every once and a while
Leech socks are pretty effective as the seal off the at the knee and physically prevent the leeches from getting to you, but they may be uncomfortable.
I've heard citrus juice works. I've never tried it, but to me it sounds made up.

The sprays will deter, the salt will make them leave, and the socks do nothing but prevent access.
Comment: Any evidence for the tobacco water story? I've heard this one as well, but have never verified it.
Comment: @LBell I've not found any scientific proof, but Google presents quite a few references to the trick. Apparently it's quite popular.
Comment: It might be worth mentioning that tobacco water, if strong enough, can make you dizzy from the nicotine. Tabaco absorbed through the skin isn't particularly dangerous, but it could make you uncomfortable.
Answer: I know this is a bit late, but having had a lot of experience with leeches makes me believe I can add some value here.

Salt works for both avoiding and for removing leeches. The method to apply is take a good amount of salt onto your palm, add a few drops of water to just make it a bit of a paste, and then, marinate the sides of your shoes and the top portion with this paste. Leeches won't climb beyond the salt line. You can apply the salt paste on your legs and socks as well. Reapply if the paste washes off as you cross streams or if it is raining. Most try to apply dry salt on legs and the salt doesn't stick and falls off. Hence many do not know how effective salt is for prevention. Most know salt as a leech removal agent (which it is as well).
Tobacco - Does not work. At best, this forms a super smelly companion for you. Your trekking shoes, pants and socks will be smelly for a really long time after this.
Deet works. This needs to be reapplied in case of a rainy trek.
Leech socks - super uncomfortable. Partially effective. The effectiveness depends on how tight one ties the knots at the upper end of a leech sock. Also, these do not prevent the leeches from climbing on to you. They just make the leeches leave your feet alone and climb higher up (any warm place that they can find).
Antiseptics like Dettol spray. These help to get rid of the leeches that have already climbed on to you. Spraying these will also keep the leeches away for a small amount of time (the spray tends to get washed off easily).
Slaked lime paste (lime paste) - Does not work. At best, it'll burn your skin a bit :)

Having said this, if you are wading through a thick jungle, you will end up with leeches on your body from the plants around you. So none of these methods will help. The above mentioned methods are only for leeches that climb up from the ground. For those that are on the leaves and bushes, your best bet is to use a deet spray or dettol spray to get them off you.
Note: I've tried all of the above methods. I'm a frequent visitor to leech infested forests.
Comment: It's never too late to add a great answer! Thanks for the additional information!
Answer: Use salt as it helps remove leeches. ( I know it works I have personally seen it work and it honestly does dry them up.) You could also just leave them to fill up and fall off and then they are gone. The biggest worry though is probably infection for incorrect methods of removal.
To prevent leeches I recommend leech socks or pants as they really work but are a bit uncomfortable. Also use stockings (wear stockings). And spray yourself with insect repellent and eucalyptus oil.
Answer: Leeches found in tropical climates were found to drop off from the bite site if some salts are sprinkled over it. This is a very effective way to remove them. I had experienced this myself when I was in the southern state of Kerala, India for trekking. Unfortunately, it took over an hour to stop the bleeding from my finger. I noticed leech's reaction from salt poured over it was spontaneous and it seemed to die later from the salt. However, there is a possibility of its tooth getting stuck in the process and  remain attached to the abrasion and this can cause itching/swelling and subsequently infection if not treated immediately. You should never attempt to pull it from the skin as this will cause bleeding and its residue to remain attached to our body.
Answer: I was given some horrible smelling perfume, had it in my bag and with one tiny squirt the leech fell off. The next time I went down to the dam, I sprayed it on my legs and ankles, never got a leech, although people with me did!
I don't know if it's the smell, or the alcohol in the perfume, but it works for me.
Answer: From my personal experience trekking in the jungle, if the path you are walking on is infested with leeches, there is no way you can avoid them.
Leeches get excited with the vibration your foot steps create, and will hang onto your shoes when they get the opportunity. Then you absolutely do not feel them climbing on your skin, nor feel them biting you.
Socks are absolutely helpless. I have tried wearing 2 pairs of socks. High shoes or boots are helpless too.
I found salt didn't work.
What worked well was spraying this mosquito repellent on the leech. It was a spray I got from the supermarket. It has citrus juice in it and that is what repells leeches away I believe.
Spraying twice would make them drop their grab. You then only bleed a little.
Also you should not panick having leeches on you as they are said to suck out the toxines you have in your blood. They are said to bring good to your blood. You won't die from leeches bites.
The thing to avoid is to panick and attempt to pull out the leeches with your fingers.
This is based on my personal experience (in south east asia). Leeches were small.
Now there might be some nasty leeches in other parts of the world (south america) more difficult to handle.
Comment: Leeches may be used for medical therapy but those animals are cultured under well observed conditions. The leeches biting you in the jungle may have diseases which could harm you the host, too.
Answer: If you can observe clearly , you can easily differentiate the two ends of a leech .. the mouth/head part will be thin and the back/tail part where it releases gum to stick will be thick. To remove a leech place you two thumbs on your body such that leech mouth is in between them , now start applying force with your thumbs by pressing hard into your body ... the blood pumps into leech more than required and it starts lifting its head part .. now just flick it away ..
Never use does / lighter / salt / other sprays on sucking leech , these will make leech vomit blood and at times it may vomit into your body.
Never flick away leech while it is sucking blood .. if its teeth get stuck into your body .. you will get infected...

How do I avoid leeches?


ATI driver installation failed

Question: I tried to install the driver for my ATI Radeon HD 4330 graphics card from the AMD website. I have Ubuntu 13.04 on my HP laptop. After reboot I don't have the launcher and the borders of the windows. Can you please help me?
Answer: Go to TTY console (Ctrl+Alt+F1) and after login write "sudo apt-get autoremove fglrx --purge" and then "unity --reset" and "sudo reboot". After reboot, things should start working and try reinstalling the driver or installing another driver. If after installing the next step of drivers gives the same error, repeat the process of the TTY console.

ATI driver installation failed


How do I stop a Blaze spawner from spawning blazes?

Question: I want to make a Blaze farm but they keep spawning even if I put torches on the sides .  What can I do to stop them spawning?
Comment: The only way to stop blazes from spawning would be to place torches all around the area as blazes can spawn even in pretty high light levels thus, you would have to place a torch approximately once every 2 blocks or so. However, it would be better if you would just take the extra precaution to place one torch every block
Answer: What blocks immediately neighbor the spawner is irrelevant, it will still try to spawn mobs across its area of influence.Spawners place mobs at three levels - one below, the level of the spawner, and one above, and can spawn mobs in the air. Horizontally mobs spawn anywhere (not aligned to blocks, just anywhere) within 8x8 meter square centered at northwestern corner of the spawner (one with lower coordinates). So you'll need to light up four blocks in every direction, and don't forget the layer above.
Blazes spawn at light level 11 or lower.
Torches give light level 14, so one torch blaze-proofs two blocks in every direction (diamond-shaped) on the given level, or one in every direction if it is one level below, or just the block above itself it is two levels below...
To hell with it, it is much simpler to just show:

Note different floor levels.
Taken from here.
Comment: Note that blazes from a spawner will also spawn in mid-air, and the spawn area is wider than the little platforms the spawners are found on. So even filling the platform with torches, they will still spawn outside the balcony if there is space. (Source: fiery experience!)