What does a person's patronus imply about their personality?

Question: Harry's patronus is a stag. It pretty obviously is a direct reference to his father's animal form (His father's patronus was also a stag). Hermione's patronus is an otter, and Harry's mother's (and Snape's) is a doe. Does these imply anything about personalities? What are the factors that may lead to the form that a corporeal patronus will eventually take?
Comment: I'd lean towards absolutely nothing. Most of the examples of corporeal patronus forms in the books are affected by things other than personality traits; Snape's doe and Tonks's werewolf, for example, represent the people they loved most. In the case of James Potter, his patronus matches the form he takes when transforming as an Animagus. Dolores Umbridge has an almost obsessive love for cats, and if I recall correctly, her patronus was a cat; perhaps Hermione had a similar affection for otters.
Comment: Ron's home, the Burrow, is near Ottery St Catchpole. Ottery meaning 'on the river Otter'. Jack Russell's are supposed to chase otters. Hence ...
Comment: Hermione's patronus is an otter because of the otter's relationship with a Jack Russell Terrier. Which is Ron's patronus.
Comment: @AnthonyGrist [Gasp!](http://img.thesun.co.uk/multimedia/archive/01473/otter1_1473816a.jpg) How could she not?
Answer: There's no precise canon answer, but some tangencial information that may have some bearing:

.

Q: Does the animal one turns into as an Animagi reflect your personality?
JKR: Very well deduced, Narri! I personally would like to think that I would transform into an otter, which is my favorite animal. Imagine how horrible it would be if I turned out to be a cockroach! (source: Rowling's America Online chat transcript, AOL.com, 19 October 2000)

While the quote is about Animagi form, we know that they 2 are somewhat related (most if not all known Animagi have the same Patronus as Animagus form - Prof. McGonagle, James Potter are 2 I remember off the top of my head).
Also, as has been discussed previously, JKR indicated that falling in love can affect one's Patronus. Whether you consider that part of "personality" is kind of subjective.

On the other hand, some Patronuses seem to have zero relationship to their caster, such as Ron's:

MA: What's Ron's Patronus?
  JKR: Ron's Patronus? Have I never said that either? Oh no, that's shocking! [Laughter.] Ron's Patronus is a small dog, like a Jack Russell, and that's a really sentimental choice, because we've got a Jack Russell. He's insane.
  (source: Anelli, Melissa and Emerson Spartz. "The Leaky Cauldron and Mugglenet interview Joanne Kathleen Rowling: Part Three," The Leaky Cauldron, 16 July 2005)

Quite clearly, Ron is NOT insane :)
Comment: On the other hand, dogs are quite loyal.  That seems to describe Ron rather well.
Comment: So could it be implied that Wormtail *wante* to become a Rat? Or that he became a Rat as that suited his personality?
Comment: @BorhanMooz - I interpret it as the latter.
Comment: @Möoz What does Pettigrew have to do with Patronuses? And depending on definition of 'insane' I would say that Ron could be actually 'insane'... But not really, no.
Answer: Oh, as far as the relationship between otters and Jack Russell terriers, apparently the dogs are known for chasing otters?  That's what I've read elsewhere.
It really does seem to me that everyone's Patronus represents them in some way.
Otters, like Hermione's, are clever (they use tools like rocks to break into their food and can handle puzzles) and inquisitive. Clearly that's pretty suitable for Hermione!
Luna's is a rabbit, which has a host of sybolism.  In Japan it's associated with the moon (like her name); one source says that in Kerry, hares were thought to hold the souls of the villagers' grandmothers, and Luna could be said to be an old soul; they're a symbol of fertility and new beginnings, and the "new beginnings" part seems to fall very much in line with her personality somehow; and finally, rabbits are born with their eyes open so superstition says they hold powers over the evil eye, and of Luna it could be said that her eyes are more open than others', both to the creatures she believes in which nobody else does, and to the nature of the people and the world.  She's pretty aware.  So I'd say her Patronus is really fitting, as well.
Ginny's is/was a horse, and horses are thought of as spirited and free, which matches her personality.  I can't find it now that I'm looking, but I read once a superstition that said, "because horses can find their way in the dark, people believed they could foresee danger or could guide souls through the underworld."  If I tried I could probably spin together something about how she "found her way through the dark" time that she was under Riddle's diary's control to become the confident person she later was, and that she "became a guide" to Harry in his own dark times by becoming one of his closest friends and then his wife.
Lupin's is easy enough:  Not only does his family seem to have some kind of affinity with wolves (assumed because of their names), but because of his condition and the way it's treated in the wizarding world, it is pretty clear that his werewolfishness is something which causes him some great consternation.  He resents it, but he can't separate it from his personality as a whole; to him, the werewolf is who he ultimately is, and what he's a slave to.  To his mind, it's not only a representation of himself, but also his entire history and maybe his fate.
I do not even know what is up with the Potter family.  Harry's Patronus was a stag before he knew that his dad was an animagus, so it was independent of that information - but was James's Patronus a stag before or after he could turn into one?  Was Lily's Patronus a doe before or only after she fell in love with James?  The Potter family is just hemorrhaging deer, it's crazy.  Deer are agile and difficult to capture, though, which fits with the family's association with Voldemort... and there's a lot of dignity to a deer in mythology, especially in its association with the forest, as there seems to be much dignity attributed to the Potters, as other wizards speak of them.  But seriously, this group gives me some trouble.
In general, though, I think it can be said that there is a lot of evidence to support a person's Patronus being a reflection of some intrinsic part of their character or personality.  It's that way with a large enough sampling of the characters with known Patronuses to feel like a pretty good bet.
Comment: Rabbits are born with their eyes closed. *Hares* are born with their eyes open.
Comment: I disagree that his family has an affinity with wolves; the surname is just a way of giving the readers a hint. It's clever and not at all the only example. The Arithmancy teacher? Septimus Vector. Herpo the Foul? Herpetology. There are many other examples too. Your last paragraph I agree with fully. And I like the parallels you draw - all well done. Especially Ron/Hermione. Those are quite fun.
Answer: The Patronus, represents that which is hidden, unknown but necessary within the personality.
Rowling's Pottermore writing about Patronuses, includes some quotes from Charms of Defence and Deterrence by Professor Catullus Spangle.

No reliable system for predicting the form of an individual's Patronus has ever been found, although the great eighteenth-century researcher of Charms, Professor Catullus Spangle, set forth certain principles that are widely accepted as true.
The Patronus, asserted Spangle, represents that which is hidden, unknown but necessary within the personality.

'For it is evident,' he writes, in his masterwork 'Charms of Defence and Deterrence'… that a human confronted with inhuman evil, such as the Dementor, must draw upon resources he or she may never have needed, and the Patronus is the awakened secret self that lies dormant until needed, but which must now be brought to light...'

Here, says Spangle, is the explanation for the appearance of Patronuses in forms that their casters might not expect, for which they have never felt a particular affinity, or (in rare cases) even recognise.
Pottermore - Patronus Charm
Answer: I was discussing this with a friend lately and it might be that Hermione's otter Patronus is a reference to Ron.
The Weasleys live in East Devon (hence supporting Chudleigh Cannons), and it's implied that it's in the Otter Valley since the nearest village is Ottery St Catchpole...
Comment: So, what does that imply about her personality?
Comment: @phantom42 - presumably, that she's attracted to Ron. Even before admitting it.
Answer: I've been lead to believe that a person's patronus is dependant on the person they love the most dearly.

Ron's patronus is a Jack-Russell Terrier, which are known to chase otters. Coincidentally, Hermione's patronus is an otter. This reveals that Ron had had a crush on Hermione in The Order of the Phoenix, or even earlier on in their school lives.
Snape's patronus was a doe, like Lily's, because he loved her so much and her death affected him enormously. Like Tonks, his patronus changed to reflect the person with whom he had a strong connection.
Tonks's patronus became a wolf after she met Lupin.
Harry's patronus was a stag like his father's, because of his resemblance to James, in appearance, personality, and interests (like Quidditch).
Comment: Love? I think not here: **Never forget, though, that one of the most famous Patronuses of all time was a lowly mouse, which belonged to a legendary young wizard called Illyius, who used it to hold off an attack from an army of Dementors single-handedly.** (From Pottermore)
Answer: I think that, in Harry's case, it's because he loved his dad, even though he hadn't met him. In Tonks's and Snape's case, their love was unrequited: Remus in Tonks's case and Lily in Snape's. If, say, Snape started to fall for someone else, would his patronus change too?


Does Femme Fatale target exactly 1 ice, or all with same name?

Question: If the corp has multiple copies of the same ice, Wall of Static for example, and the runner plays Femme Fatale and chooses a Wall of Static for its special ability, does that mean the runner can use Femme on all Ice named "Wall of Static", or just the one specific piece of ice that they chose?
Comment: Actually, I hit approve on the pending edit that removes the social bits ("Hey" and "Thanks"), but we should also change the question title to be more descriptive ("Does Femme Fatale affect all ice of the same name as the one chosen?"), and point out that Wall of Static is just an example ice, and not really an important part of the question.
Answer: It's just the one. When a card in Android: Netrunner is referring to multiple cards of the same name, it'll refer to them as copies, e.g. Copycat. There are also other examples.
Answer: Femme Fatale targets a specific piece of ice, not ice by name, it can even target ice you don't know the name of (unrezzed) in which case how would it let you get past other copies of the same ice. If Femme allowed you to bypass all ice of the same type it would only be able to target rezzed ice (so you could know what ice you are allowed to bypass, and refer to bypassing that ice and all copies of that ice, or would allow you to name a piece of ice, allowing you to bypass all ice with that name.


Ubuntu 12.04 - Trouble with UFI Boot on Macbook Pro Retina (late 2013)

Question: I used the following tutorial to set up Ubuntu 12.04 as dual boot on the Macbook Pro Retina (late 2013):
I did followed this article
It sets up Ubuntu as dual boot with EFI Boot only (without Grub). However, I have some issues with the boot configuration... According to the tutorial, the boot manager (ReFind) needs a kernel on the HD of Mac OS X to be able to find it, so I copied the kernel files from Ubuntu to MacOS X in /EFI/ubuntu and provided the information to the boot manager as described in the tutorial.
However, in my case, ReFind can boot the kernel but it fails to boot at the end since it cannot find the folder /dev/disk/by-uuid and boots into the initramfs shell. Creating the folder manually and providing a syslink with the UUID as name, linking to the correct partition (in my case ../../sda4) lets me boot Ubuntu.
Only Problem is that I have to do those settings each time I reboot. As soon as Ubuntu is loaded, the /etc/disk/by-uuid folder exists as well as the /etc/fstab (which does not exist when booted into initramfs). But when I reboot I can only get to the initramfs shell again and have to create the folder and syslink again.
So not really sure what is happening there. Does anybody have idea?
It seems like the /dev/disk/ I get access to from the initramfs shell is not the one of the actual Ubuntu. Is this possible?
Answer: You need to boot in to OSX and install rEFInd in OSX, Macs dont reconize any version of linux by default, so your need to install it on your OSX partition. After that you reboot your mac and rEFInd should pop up
Comment: He did, his problem is other.


What happens when the conductance of a sodium channel increases?

Question: My intuition is that, since the concentration of sodium within a cell is higher than the extracellular concentration, when conductance increases, this corresponds to the channel being open and means sodium will enter the cell. Is this correct? And what impact will this have on the membrane potential?
Answer: No, not quite. You are on the right lines, but incorrect in thinking that intracellular sodium concentration is higher.
At the resting phase of a neuron, there is less sodium inside the cell and more sodium outside the cell. An ATPase sodium potassium pump is constantly pumping 3 sodium ions outside the cell for every 2 potassium cells that enter the cell.
For voltage gated sodium channels to open, there must be a significant change in voltage, which can be triggered by the binding of neurotransmitter to receptors for example. This triggers the sodium channels open and sodium will flood into the cell due to a high concentration gradient (because there are more sodium outside than inside) but also due to an electrical gradient (the neuron is more negative on the inside; positive sodium ions will be attracted to the inside).
Because sodium is flooding into the cell, this will cause the membrane potential to become more positive (depolarised) and will eventually reach an action potential (30mV). After an action potential, the channels will become de-activated and shut. After a period of hyperpolarisation, the neuron will return to a resting state.
Source: https://en.wikipedia.org/wiki/Action_potential


PCI SATA controller recommendation

Question: I want to add a couple of SATA drives using a PCI SATA controller. Do you have any recommendations for me that will work with 12.04?
Comment: Can you use PCI-Express 2.0 x1?
Comment: No PCI express please.
Answer: First let start by saying that SATA PCI cards are hard to come by.  But take a look at this card here.
It states that it has Red Hat Linux, SuSE Linux, Linux open source code.  I can not find out if it has been tested with 12.04, but this site here has tested the cart with 7.04.
I know this may not be the answer that you are looking for, but I could not find any other information or cards :).
I asked some of the guys that I work with, and I was told that if the card works with 7.04, that it should work with 12.04. but there is no way for me to verify that, I hope that you understand

PCI SATA controller recommendation


Should questions about building codes and electrical codes be considered on-topic?

Question: Should questions about building codes and electrical codes be considered on-topic?  StackExchange sites usually shy away from narrowly localized questions, but building and electrical codes have many commonalities within the United States.  And knowing the answer even for a different locality than your own is informative: at the very least, it helps you find the terms to search for in your local code.
Answer: I think they should be on-topic but have to be tagged with the location.  Otherwise people will not know that they have to keep to codes.
Comment: I think _answers_ should specify location.  The _question_ can be more general and collect answers for different localities.
Answer: I'd be erring on the side of caution and saying "Off Topic" - as you said, they're SO localised.
And I don't mean any offense to anyone, but the fact of the matter is that a lot of people forget that there's a big wide world out there and that their codes may not be the same as someone elses.
For example, I saw a question regarding rewiring electrical sockets, and the colours they used for the wiring are different to the colours we use in Australia, which may cause problems if I were an Australian coming on here and seeing "Oh, look, brown = neutral" when in fact brown = active.
Comment: Brown = neutral?? Best not come to Europe, then!
Answer: At the very least these must be tagged.
Power is especially tricky, not least as in some places it's illegal to do unlicensed electrical work.
The site should definitely have a large disclaimer somewhere disavowing responsibility for breakage, damage, injury or death...


Frame rate issue-pro tools

Question: Unsure about a frame rate issue.
I'm working in Europe using PAL.
I get a lot of quicktime video files (inc guide track) that have a frame rate of 29.97.
This is not NTSC.
I don't use an external monitor. I set the frame rate to 29.97 in the setup page in Protools. It will show red if I don't match to the same rate.
I have a few questions. If I don't use an external firewire monitor does it matter whether I change this frame rate rate or not.
When I send the bounced master track back to the video editor does he not have to play the final video for broadcast at 25fps.
Would this not cause a mis match.
I'm confused as my audio matches the omf that the video editor sent but she says that it is out of sync with their picture.
Anyone have any ideas?
Answer: 29.97 is NTSC. A lot of editing programmes seem to set themselves to NTSC as a default and sadly a lot of editors don't seem to realise or notice this.
Answer: If you're working with an NTSC reference video for a program that's supposed to be in PAL, you're going to run into problem...i.e. that sync issue you mentioned. The first thing you should do is check with the editor to confirm what the program's final format is supposed to be. If it's truly PAL, and they sent you an NTSC file (which 29.97 is), then they need to send you a video, AND OMF, with the correct frame rate. If, as Ian suggested, their timeline is set to the incorrect frame-rate, there are potentially larger problems waiting to happen on the back end of the project. Get that workflow sorted out before a ton of confusion hits!
As to the frame-rate setting...yes, it matters. Depending on the audio format you output, there may be a frame-rate stamp in the metadata of the file. The video editing software will notice this, and it will affect the playback rate of the file. Unfortunately, 1 second real-time does not always equal one-second in video time...especially in NTSC. Get everyone on the same frame-rate: editing software timeline, reference video and OMF, and DAW session. This will prevent sync drift (non-matching start and end points) and slippy internal sync (timing differences between audio and video elements, even though start and end points match).
Note: If the editor is using Final Cut, there are some other potential problem points that I can explain. It may be unnecessary though. Start with the frame-rate problem and see if that takes care of things.

Frame rate issue-pro tools


Rose doubt - is this a fungus?

Question: I have recently bought a potted rose plant and now its leaves have turned variegated. It was a nice bottle green (uniform) when I bought it first.
Thank you in advance for your help!
Comment: What did you do with the rose after you bought it? Did you plant it outdoors? What variety of rose is it? Have you had it in the house? More info please, including photos of the whole plant if possible....
Comment: Hello bamboo, thank you for your reply. It is about a month since I bought the plant. It was in a very tiny pot (about 5 inches diameter) so I re-potted it in a larger pot. Now some new leaves are growing (from the top) but absolutely unlike the healthy ones I bought it with. Here is the full picture of the plant, it is about 1.5 feet tall.
Comment: Link to the full plant image: http://i.imgur.com/dDB8rOZ.jpg
Comment: I have placed it on the rooftop where it gets about 5 hours of sunlight. DO let me know if you need some other details.
Comment: One other thing - what part of the world are you in, oh, and what soil is it planted in - ordinary garden soil? Potting mix? Looks lumpy in the picture, and very pale in colour (the soil)...
Comment: I am from India and it is tropical climate here. Right now it is around 18-20 deg.C. Yes the soil we get here at my place is lumpy indeed. Do you think that can be the problem?
Answer: I'd take it back for a replacement if I'd only just bought it. Depending on where you live, trading standards would mean that even purchasing a plant needs to be fit for purpose. A diseased or poorly one is not.
Answer: The problems with your rose plant appear to be cultural as much as anything else - I would suggest you buy some decent potting soil if you must keep it in a pot, but bear in mind that, unless the rose is a miniature or patio variety, most hate being contained in a pot and don't do well, particularly after their first year, because they want to put down deep roots. The trouble with using soil from the garden or just from outdoors is it may have pathogens within it, and whilst plants cope with things like that actually in the ground, when you put the soil in a pot, there's nowhere for the pathogens to go, because its contained in such a small space. That alone may account for the problems you're seeing, but it may also be that the soil is poor in terms of nutrients. Roses like heavy, fertile soil conditions, growing best in rich, clay soils, and do not like to dry out completely, though drought conditions usually don't kill them, they just don't grow and flower very well. They are also a high maintenance plant, being prone to many fungal infections and insect infestations, and its usual to either use a preventative spray regime fortnightly during the growing season (with a combined fungicide insecticide such as Roseclear Ultra) or to inspect regularly and treat with either a fungicide or an insectide, depending on any problems seen. They also benefit from feeding in early spring and again about 8 weeks later with a specialist rose food to help keep them strong to resist all the pests and diseases they're very prone to get.
If you know that your rose is a reasonably small variety, and you want to continue growing it in a pot, on the assumption you can buy something decent to grow it in, take it out of its pot, brush off any soil you can without damaging the roots, rinse the roots in a bucket of water, clean the existing pot thoroughly, fill up with the new potting mix and replant the rose, watering well. Then I suggest you prune back to healthy growth, to an outward facing bud, and start a proper care regime as already mentioned. If you're wondering what potting mix you should use, I would recommend John Innes No. 2 or 3, but I've no idea what's available where you are.
Comment: I would add a specialist rose mycorrhizal fungus dusted over the roots pre planting, if you have kept it. This will give your rose the added bonus from the root/fungus symbiotic relationship. Establishment of a large and good root system will be quicker, giving you a healthy more robust plant.
Comment: @Rosie - that'll only work if its in the ground, it can't establish a great root system stuck in a pot, though the fungi might help it recover from its current condition, possibly
Comment: Thank you bamboo for your very detailed tips! Though not all you mention is possible at my place, I surely followed some of the tips like pruning it back till healthy growth, spraying insecticide + fungicide and replacing part of the soil with an organic manure mix, also adding some rose food. Now waiting for the new leaves to come up.
Comment: Thanks Rosie, I'll keep in mind about the mycorrhizal fungus tip!

Rose doubt - is this a fungus?


Could life develop above a planet's atmosphere?

Question: Imagine a planet with extremely low density, and thus low gravity and an equivalently thin atmosphere, but a very active and strong magnetosphere that prevents solar radiation from destroying complex molecules or stripping the remaining atmosphere away. Imagine that, as much as the previous statements allow, it's earth-like - readily available organic-molecule building blocks, in the star's habitable zone, and liquid water. Now imagine that the very basics of life drop on this planet from a comet or something - basic self-replicating molecules, no more. Given these conditions, could life somehow extend itself to grow above the upper reaches of the planet's atmosphere (i.e. plantlike structures with "stems" or "trunks" outside the atmosphere, and more mobile life living in the "branches"), and what would it look like?
Comment: I don't understand what you mean by low density = low gravity (does Saturn have low gravity?) and then it's somehow Earth-like. Could you perhaps provide numbers instead of vague hints? What about a planet that doesn't have an atmosphere but is covered by a sheet of ice? Otherwise, I'm afraid you are just asking if a space elevator could grow and even develop naturally which is practically impossible
Comment: In a low gravity world, atmosphere will be more spread out that on Earth ([Barometric formula](https://en.wikipedia.org/wiki/Barometric_formula)). Plants (or any other structures) will _always_ have a much harder time climbing out of the atmosphere than tiny gas molecules.
Comment: For low density = low gravity, I was imagining a planet that's slightly smaller than Earth, but with much less mass, providing lower gravity. I don't really have hard numbers for this, leaving it open for someone to select what they need. As for "Earth-like," I meant in terms of it being a planet as I stated, and not a gas giant like Saturn.
Comment: Life is about rearranging chemicals into a copy of itself. There are no chemicals above the atmosphere. The only thing plants can get there is exposure to the sun, but they will still need roots in the ground. But they can get their sun within the atmosphere, without the need to protect the plant from cold and dry space. The only reason I see to grow out of atmosphere is avoiding the shade from other plants.
Comment: I don't see any reason why "smaller and less-dense than Earth" and "strong magnetosphere" would be incompatible. Maybe this planet is "younger" in the galactic scheme and has a more active core, maybe the core is iron-rich but the crust is almost devoid of heavy metals...I'm fairly sure it's possible.
Comment: Have you ever heard of the term "Minovsky physics?" It's a concept for worldbuilding - basically, you assume one impossible thing with strict rules to it, and then build a realistic physics system on the rest. It helps if the thing isn't too unbelievable to the average reader. It's FTL travel in most sci-fi, or the existence of magic in fantasy stories - basically, it's the one thing that makes the world "not ours" and worth telling a story about without breaking suspension of disbelief. I'm asking this question to determine HOW far I'm stretching that suspension.
Answer: I suspect a plant can't grow anywhere near that tall. Mainly because of a combination of these 2 factors:

The trunk or stem at the base of the plant has to be composed of something strong enough to support the weight of the rest of the plant above it.
Atmospheres are really quite deep. Earth's atmosphere is 480 km thick.

The 84m tall Giant Sequoia called General Sherman is estimated to weigh 2100 tonnes. If it grew to 480km tall the wood at the base of the trunk would have to support 2100 tonnes x 5714 = 11,999,400 tonnes. (This assumes no branches other than the ones General Sherman has now).
Comment: Worse making the atmosphere less dense and thus deeper just makes the problem harder.
Answer: Floaters.
1:  Lots of atmosphere (thick atmosphere)
2:  Atmosphere is a heavy gas (e.g. CO2, NO2, H2O)
It would be easy to be buoyant in such an atmosphere regardless of gravity. If you had this in a low gravity scenario buoyancy does not change but you would not be crushed at ground level under the weight of the thick atmosphere above you.
Now let us take a page from the book of holopelagic seaweeds. - seaweed which is never rooted in the ground but which drifts freely with ocean currents.

http://arlohemphill.com/2011/08/26/change-is-in-the-air-seaweed-seaweed-everywhere/

In the North Atlantic Ocean, Sargassum algae has evolved a completely
  pelagic existence, free-floating on ocean currents of the Gulf of
  Mexico, Caribbean and the Sargasso Sea. Mariners have documented large
  drifting islands of this seaweed for hundreds of years, mistakenly
  believing the appearance of the plant to be a sign that land was
  nearby. Their false assumption was that the seaweed had been torn from
  reefs and shoals during heavy storms. With other species of Sargassum,
  found throughout the oceans of the world, the seaweed indeed is
  usually affixed to rocks, reef and such. But two Atlantic species have
  made the evolutionary leap to become "holopelagic", meaning they
  permanently live and reproduce adrift on the sea.

Your high atmosphere plants live there.  They have built in floats like the sargassum, but "air" floats like balloon organs.  They drift around in the top layers of the atmosphere, forming great cloudlike mats which your other organisms can inhabit.  Perhaps these plants can change altitude some, ascending in the day and descending at night like jellyfish.  The adults obtain all they need from the air, reproducing vegetatively.  Seeds fall to earth below and young plants take off when they grow big enough to become buoyant.

Your question was about plants that are outside the atmosphere - presumably held there by some towerlike trunk below.  My problem in thinking about that - the atmosphere decreases gradually. It is not like the ocean where there is a surface.  You have gas in decreasing quantities for a long way up.  A floating creature or any balloon must have atmosphere to float in and it will cease to ascend at a given height.  Which might be very high.
Answer: Basically what I'm getting from the others answers is that its not possible, and I tend to agree. I don't think a tree could support it own weight that tall.
However if we attack this problem from another angle...
Your planet has these truly massive tall trees, just bumping up against the boundary of impossible. To get them even farther up high, they are on plateaus that are very high above sea level. Or maybe they're even really tall mountains. High rainfall would be required, but lets say your planet has that in those areas.
Then, something happens to the planet where it's losing it atmosphere, so that brings the level down. What that is I admit I don't know, but maybe someone else can help you out with that part.
Between all these things together that might bring you to just about the height you want. I would imagine, maybe, the part of the tree that sticks out of the atmosphere might die out, but everything that leads up to it could still be alive.
Comment: You'd have to carefully construct your planet so that it was hot enough at high altitude for precipitation to fall as rain not as snow (even tropical mountains like Kilimanjaro have snow on their peaks), yet at the same time not so hot at sea level that it is uninhabitable.
Comment: @DrBob. Good call, doc!


Do Tinkers like the one from "Willy Wonka and the Chocolate Factory" still exist?

Question: I just wonder if "Tinkers" like the one in "Willy Wonka and the Chocolate Factory" who has a cart of meat cleavers still exist to this day?
Answer: In the UK, It's possible that there are one or two still in operation but it's more likely that these have died out.
In the past, people didn't have access to high quality knives or sharpening equipment and a these knife grinders / tinkers could travel from town to town making a living.
With the advent of higher quality (and cheaper) steel and home sharpeners (especially the electric type), the need for itinerant workers like tinkers fell away.
Commercial sharpening firms (for hotels / restuarants / butchers etc) do exist but these are generally "bulk" deals rather than a home service for one or two knives although many will offer the service if you call in.
Comment: The trade still exists - I used to live-in at a hotel where my partner was chef. The 'knife man' would come round every few months to re-edge the entire kitchen staff's knives [pros don't risk their own very expensive blades on domestic sharpening kit]. He had a transit van rather than a horse & cart though ;)
Comment: I was thinking of adding a note about commercial sharpeners (to the trade) but it seemed redundant.
Comment: In India blade sharpener still exists. They come on cycles and you can give them blades to fix. [Like this one](https://i.ytimg.com/vi/bNDIG7BcAHI/maxresdefault.jpg)
Comment: Google maps finds 5 in London - not exactly as common as sandwich shops, but still there ;) They'll come to your home to do it, but at a price - £40 for up to 8 knives, then increasing with each additional blade.
Comment: I've just had a card for a mobile tinker come through my (UK) letterbox - knives £1, lawnmower blades £5, etc.
Comment: In Los Angeles, at our local farmer's market every Sunday there's a tent set up where you can get your knives and scissors sharpened.


Can the Czech Republic revoke a UK driving licence and impose a ban?

Question: If a UK citizen residing in the Czech Republic receives a driving ban for a minor offence (not displaying a front numberplate) and he holds a UK driving licence, do the Czech authorities have have the power to revoke the UK licence and enforce the ban?
Comment: Generally speaking, only the issuing authority can revoke the license. The Czech police can fine you and impose any other penalties as per the local law. I am not sure if the UK has a reciprocal agreement over traffic violations, if it does - you may find the appropriate penalties levied to you by the competent UK authorities as well.
Answer: First of all, not displaying the front numberplate is by no means a "minor offence". It renders all kinds of automated traffic enforcement devices (speed cameras, red light cameras at crossings, etc.) completely useless. You could thus be speeding at will and ignoring all red lights without any fines, unless the police managed to chase you down.
A driving ban ("zákaz řízení") effectively renders your driving license useless in Czechia. If you ever drive again in Czechia while under such a ban, you're commiting a crime ("maření výkonu úředního rozhodnutí) for which you can be imprisoned for up to two years (plus removed from the country and banned from re-entering).
Such a ban probably has no effect on your right to drive in the UK (there would have to be an international treaty specifying that), but IANAL.
Comment: This is the same rule followed in the USA. New Jersey cannot revoke your New York driver's license, but they *can* revoke your right to drive *in New Jersey*. As state lines cut across major urban areas all along the US east coast (and even divide neighborhoods in some areas), this is more of a barrier than you might think. On the west coast, it isn't so bad to have your driving privilege revoked somewhere (e.g. living in San Diego, CA, banned from driving in OR), but there are fewer opportunities for it to happen since most people aren't crossing state lines just to get lunch or go to work.
Answer: Czechia has the power to ban you from driving in Czechia. But Czechia cannot revoke your foreign license.
In any case Czechia could choose to notify UK about that offense and so UK will eventually decide independently and eventually UK will revoke your license.
This depends if CZ want to do something, UK want to handle the thing, and how minor UK will consider the offense. Often only major offenses go to the final step, but this is very dependent on both countries, and how each countries consider problematic an offense.
Comment: I'd like to add that EU and connected European countries use several interconnected systems for sharing traffic violations, driver's licences and vehicle information, so it is possible for Czech police to check your driver's licence online and your violations are shared to your home country. What is or isn't done specifically I don't know (as it changes overtime based on bureaucracy).


What metals will a culture most likely use if use of iron is prohibited?

Question: What metals will a culture most likely use if use of iron is prohibited but it has advanced technology?
Comment: why *is* iron prohibited?
Comment: They will use **Purified Iron**.

Purified Iron involves a long and expensive routine to remove all religious impurities from common iron and make it safe for usage.

Of course, touching Purified Iron will quickly taint it. Therefore only the High Priests and their elite bodyguards can safely use it.
Comment: When the benefits of iron outweigh the risks of defying the prohibition, the engineer will resort to black-market iron.
Comment: Please specify the level of technology. Are we talking about a medieval world, modern tech, or something in-between?
Comment: Much like lead, iron is the final destination of many nuclear decay chains.  Maybe they have perfected fusion except have a lot of radioactive iron as nuclear waste.  I'm just spitballing here.
Comment: your biggest problem is cost, is aluminum is the only metal more common than iron on the earth but it is a lot harder to extract.
Comment: silicon is a metalloid not a metal. But yes it is way more common.
Comment: @marcellothearcane Probably something to do with the fey.
Comment: If you can elaborate on what you are using the metal for that would be good. As it stands this is too broad.
Comment: @John isn't silicon more common than aluminium?
Answer: The main problem for an iron-less advanced civilization is machine tooling.  Modern tool steels are incredibly versatile materials, capable of being forged and machined into highly complex shapes yet made hard enough to cut through most materials and durable enough for repeated hard use, such as in jackhammer bits (if you think a sword has a hard life, it has nothing on what jackhammer bits go up against day-to-day).  This is something almost no other metal or alloy can pull off -- even high-tech metals like titanium struggle to match tool steels in hardenability.
As a result, this civilization would have to develop a tool technology akin to cemented carbide very early on.  If they were able to refine a titanium-like metal to serve as an elastic matrix material, and had access to the relatively common mineral zircon as well as a supply of graphite, then zirconium carbide can be made by calcining the zircon then performing a carbothermic reduction on the zirconium oxide produced when the zircon (zirconium silicate) is calcined.  Otherwise, aluminum carbides can be formed by mechanical alloying of aluminum with graphite, and silicon carbide is another option (it can be produced by intensely heating a mixture of coke (amorphous carbon) and aluminosilicate clay in an inert crucible, or is common naturally in the universe albeit rare in Earth's crust).
Once you have carbide particles, you can then basically mix them into molten metal without too much worry about them dissolving due to their refractory nature.  The resulting cermet material is suitable for tooling due to its aggressive, abrasive cutting nature and good wear properties.  It requires an aggressive tool to machine, though, which would mean that getting started with it would be a bit...tricky.
An added bonus is that once you have a suitable machine-tool material, especially for shock-withstanding tools such as cold chisels and jackhammer bits, you have a suitable blade material as well.
Answer: Forbidding the use of iron will be creating problem mostly in civil engineering, where steel is used for reinforcing concrete.
Hardly any metal can replace iron in this case, since it is hard to find a suitable combination of tensile strength and thermal expansion coefficient.
Plausible replacements in this case would be bamboo, polymer or carbon fibers.
For the rest the culture would be using all the metals we are already using.
Comment: Bamboo or polymers can replace steel in concrete reinforcement -- but if the OP's concern is weapons, then I don't know what would replace iron/steel.
Comment: @Willow, the OP question is specifically about which metals
Comment: I was simply 'solving' the civil engineering problem... and agreeing with your answer.
Comment: @L.Dutch normally I would agree to answer the question as asked, but the weak grammar of the original suggests a language barrier, perhaps auto-translated, so suggesting other, non-metal material substitutes seems acceptable to me in this case.
Answer: Iron isn't magic; it's just cheap and easy to work.  There are lots of alternatives.
For instance, aluminum in the right alloys is scary strong; it's just more voliminous than most other substances it might replace.  Instead of this lightness being seen as a virtue, it's the source of endless bigotry; for instance no-one will admit aluminum is the best electrical conductor known by mass, some other units, and for many of the practical things we do with conductors.  And by a huge margin, e.g. twice the conductivity of copper and silver by mass, and twelve times better than copper when the unit of measure is money.  Back on track, aluminum is stronger by mass than iron/steel; it's not the only one.
Aluminum is also staggeringly plentiful; it's the 3rd most common element by mass (despite being light) in the Earth's crust (i.e. places people are likely to mine). It's everywhere, just trapped in an oxide form.   The limiting factor is the electricity used in smelting.
Carbon fiber is stronger still in both mass and volume, (and potentially even a better electrical conductor), so that becomes a silver-bullet solution anywhere aluminum is not suitable.
Where high-temp is required beyond aluminum's ability, there is titanium, palladium and more exotic metals. And let's not forget bronze.
Massive steam projects would be hard; cheap high-temp piping makes that possible; i.e. factories or ships which primarily run on steam. But those are "on the outs" anyway; a modern ship doesn't have boilers, it moves energy around the ship electrically, and either has slow-loping diesels that could be made of bronze, or jet turbines that are already made of exotics.
Fully nonferrous ships have been built; it's done in minesweepers and the famous Soviet "Alfa" submarine, built to elude magnetic-anomaly detectors.
Comment: @ankit7540 copper industry lies :)  No seriously, those charts rank the conductors **by volume**. And that only matters in armatures and some coils.  I jest, but why is "volume" talked about like it's the only unit that matters?  Elsewhere in science, it would be **mass** (aluminum wins by nearly 2:1) or perhaps molarity.  That is prejudicial because aluminum is over 3x lighter - a virtue elsewhere!    https://w3.siemens.com/powerdistribution/global/EN/tip/focus-markets/Documents/Siemens-Data-Center-Whitepaper-Aluminium-versus-Copper.pdf (Siemens doesn't make common wire)
Comment: @ankit7540 I know. But resistivity and conductivity aren't about volume, **their SI units are**.  That's not science, *just conference*:  The General Conference on Weights and Measures, which defines SI units.  (and conspiracy theories are fun, but the die was cast before aluminum entered the scene, and the *volume* unit is deeply entangled in the definition of related units). Point being, unit conventions do not define science, and when existing units don't serve an application (candela, gray) they make ones that do (lumens, sieverts).
Comment: Correction: Silver and copper have higher electrical conductivity than aluminum http://www.tibtech.com/conductivity.php, https://en.wikipedia.org/wiki/Electrical_resistivity_and_conductivity.
Comment: Since, electrical conductivity was being discussed in the first place, hence scientifically speaking and only talking about the physical parameter measured as conductivity ( or we can discuss resistance) still Silver > copper> gold > Aluminium. I don't hate aluminium, I am just trying to be correct on facts. Of-course, aluminium has other advantages as you have mentioned.
Answer: I wonder if any culture can obtain a high level of technology without iron in the first place. So this is sort of a contradiction in itself to ask this question.
Anyhow, let's examine where iron is used in modern times by humans and what replacements could be used. I am assuming that all the replacement metals are available cheaply and in excess.
Magnets
This would perhaps be the hardest to find replacement. Possible substitutes would include cobalt and nickel.
Infrastructure
Titanium could be an excellent replacement for iron when it comes to tensile strength versus weight. It would be the first choice as a building material metal and building skeletons/bridges would use titanium instead of iron. Aluminum would be another alternative for a few possible circumstances.
Everyday Items
Here again, the best replacement which comes to mind would be titanium and aluminum.
And the Achilles Heel...
All complex animals require substantial amounts of iron in their blood for oxygen transport. It is understandable to build a world where iron is prohibited from usage, but do not go on to build a world where there is no iron at all. For such a world, you would have to redesign the blood type of all complex animals or design a different respiration mechanism for them.
Comment: An organism on an iron-less world would use hemocyanins for oxygen transport...
Comment: I never said or implied that it is impossible to have oxygen transport in an ironless world. The point is that the whole cardiovascular system would have to be redesigned, along with changes at cellular level for a different type of oxygen transportation, even if you are using copper as the central metal, instead of iron @Shalvenay
Comment: Exactly. They would be stuck using silver, gold, copper, some bronze alloys and crude glasses/ceramics.  Without iron, just about all the tech that followed would be almost impossible to develop and the more exotic materials very hard to mine, refine or machine.  And without iron farming implements, they would have a much more difficult time feeding the tradesmen and idle thinkers needed to advance at all.
Comment: Don't squids have blue blood due to using another metal as the center of their heme molecule?  Copper? Cobalt?
Comment: That's what Shalvenay Mar has already mentioned. But you cannot go on using copper as the central metal in the haemoglobin without redesigning some very basic aspects of cell biology. Needless to say, it will also have a remarkable effect on the brain power of the creature considering that copper-centric haemoglobin would have different rate of transfer of blood than iron-centric. This might even be to an extent that the creature is unable to reach human-level intellect. @SherwoodBotsford
Answer: Iron can be prohibited most likely on religious reasons. For example, the ancient agyptians couldn't yet produce iron from ores, their only iron source was from meteorites. They've also seen, that it is much stronger as their copper and bronze tools. They've considered it as a metal of he gods, and they've used it in jewelry. There are even ancient agyptian jewelries where iron is embedded in gold!
Thus, a relegious reason to forbid iron is quite possible.
What they would use instead, it depends on their technological level.
First, they would likely remain in the late bronze age - it would significantly slower their technological advancement, but won't stop it.
Later they will use metal tools which are not really more rare, and aren't really harder to process them, as iron. I would vote mostly on similar metals as iron - maybe cobalt or nickel.
Later, their high tech industry would probably use our newest things - titanium, molibden alloys, and aluminium.
Note: a culture without iron surely can't produce weapons so well, as their neighbours not having this little uncommon custom. Around from the years of the early medieval ages, it would cause an uncompensible technological disadvantage in the military technology.
Compare this to our fast conquest of the ancient American civilizations. For example, Cortez with 1000 men could win the main aztec army with 300000, only because they had iron swords, armors and muskets (and horses).
Meanwhile, the main "sword" of the aztecs was from wood injected with obsidian spikes, like this. Yes, this guy on the left looks quite dangerous, but 1000 knight on the right site, full in iron, could win 300 000 from them.
Comment: I suspect that you could produce equivalent or better weapons than anything that existed in the Iron Age through something akin to cemented carbide technology...
Comment: @Shalvenay Ceramics are all very brittle. Producing good ceramics requires 2-3000K ovens, in large scale it wasn't possible even with ww2 technology. Today we use mainly still steel, sometimes titanium-magnesium-aluminium alloy if weight matters. For example, ceramic engines were once considered in car manufactury, they had made possible to produce autos working without heating.
Comment: I'm not talking about a solid ceramic monolith -- I'm talking oxide or carbide *particles* in a metal matrix here, which is far easier to make.
Comment: @Shalvenay Something like a [Macuahuitl](https://en.wikipedia.org/wiki/Macuahuitl), perhaps?
Comment: @R.M. we're talking on a far smaller scale here.
Answer: First off, why would you ever prohibit iron? It's not toxic or anything. Banning iron is like banning electricity. However, you might still be able to manage:
For cutting tools, you could use aluminum or titanium. It can form a knife very nicely (just look up "aluminum knife" on google).
For magnets, you could use nickel or cobalt. Despite being much rarer, we might be able to manage.
For building aluminum is surprisingly strong while titanium could be used. As a matter of fact, the limiting factor for most skyscrapers is not weight but actually height (it gets too hard to pump concrete up).
Reinforced concrete would be a nuisance but as discussed we could use bamboo.
Answer: It depends a bit on what you mean by that.
Scenario 1: Everyone would die. We need iron to survive. Also, let's say we wouldn't - this would ruin the economy since one would have to extract iron out of everything. There is no natural solid or liquid on this planet that doesn't contain iron. There is no substitute here.
Scenario 2: (If you just ban iron and not iron salts) Let's be non-pedantic and say our species has lived for 40k years. The use of iron dates back to about 4-5k years ago. Those are 35k years without iron. Really using iron to make useful stuff dates back to about 3k years ago - and only in the most developed parts of the world. Other cultures have discovered it much much later. Check out how they were doing basic things. Goodbye advanced technology anyways.
Scenario 3: (Not going back to the bronze age) Revolt, civil war, outside forces taking over the country/culture/whatever. Banning iron could simply not happen in our world unless the place is called North Korea or something. This again leads to everyone dying. Please be aware that at one point, iron had to be forbidden. Substitute iron with violence.
Those so far have not really been answers to your question, but please have them in mind when constructing your world.
Scenario 4: (everything goes as planned) Well, what do we need iron for? For almost everything. This goes well beyond this question. You would have to think of how to substitute iron in every single application. How many are there? I don't think anyone really knows. From construction work to machinery to cars to whatever - there is no single answer here. Iron is used in a catalyst in many chemical reactions as well as statues of famous people. Please be aware that there isn't a single answer to that question. You cannot just substitute iron with x and be happy. But it is certainly possible - and often very easy to google if you want to know how to do x without iron.
There isn't an answer to that question. But I have advice: Be aware of what you are planning and at least read the wikipedia entry of an element if you want to ban it in your story. This is really all just common knowledge, but you always have to go back to the basics with these questions ...


How likely is it to get a complete set of commons from a single booster box?

Question: I am looking at getting into MTG again. Thinking about just playing pauper and maybe some EDH. However it's kind of fun opening packs. My thoughts are I buy a box at the release of a set and just use it to build play sets of the commons.  Sell off everything else except perhaps a couple cards that may work with EDH or something. Not asking if this is the cheapest way, just whether or not it would be viable to get a full common play set from a single box or maybe two.
Comment: Kind of seems like a question for the math section - it's probability based on total commons in the set, commons in a pack, and packs in a box.
Comment: @sirjonsnow Indeed, although we have had some other questions here that were basically math questions and nevertheless seem to have been received well enough by the community.
Comment: Here is [an example of the analogous question](https://math.stackexchange.com/questions/1303673) asked on [math.SE]. Also, [this BCG question is related](https://boardgames.stackexchange.com/questions/34225), in that the underlying math seems to be the same, but the approach I took there is somewhat less practical for this case.
Comment: You could probably just buy 5 Commander pre-cons for the 100$ a booster box costs you. Cracking packs for cards is never the solution, Cracking packs to play limited is fine though.
Answer: The exact value is difficult to calculate. This is due to the print runs of the cards - the 74 commons have "print runs" of 5 to make the printing easier. There are hundreds of these, but the fact that no pack contains the same cards does complicate the calculation.
I did throw together a pack simulator to test this and it ran in the background. Below is the output after 10 million trials. The highest was 200 packs and the lowest was 45. On a different run (of about 22 million trials) I was able to get a playset in only 44 trials. This run I've let go for 35 million trials and it was only able to get that 45, although eventually I got so unlucky I needed 215 packs on one of them. The last 17 million trials have not changed the min and max, though. I don't expect them to be changing any time soon.
Thus I think it's safe to say you are never going to get a playset from a single booster box.
I modified it to check the number of boxes and found a very consistent: 2 boxes were sufficient 39.2% of the time, three boxes 58.8% of the time, and four boxes sufficient 2.0% of the time. Five boxes were only necessary on 0.03% of runs but that was consistent far far into the tens of millions of trials.
If you want to play it safe, buy 3 boxes - you'll have them all 98% of the time.
<code>new max: 72 on trial: 2
new max: 77 on trial: 3
new max: 81 on trial: 4
new low: 72 on trial: 6
new max: 87 on trial: 9
new max: 88 on trial: 10
new low: 65 on trial: 21
new max: 92 on trial: 25
new low: 64 on trial: 31
new max: 95 on trial: 42
new max: 108 on trial: 64
new low: 61 on trial: 78
new max: 115 on trial: 80
new max: 116 on trial: 110
new max: 119 on trial: 146
new low: 60 on trial: 153
new low: 59 on trial: 162
new low: 58 on trial: 222
new low: 56 on trial: 296
new low: 55 on trial: 607
new low: 53 on trial: 744
new max: 140 on trial: 2928
new low: 51 on trial: 6183
new max: 156 on trial: 9309
new low: 49 on trial: 49366
new max: 162 on trial: 60593
new max: 170 on trial: 112123
new low: 48 on trial: 117347
hit trial: 500000
new low: 47 on trial: 830525
hit trial: 1000000
new max: 186 on trial: 1307797
hit trial: 1500000
hit trial: 2000000
hit trial: 2500000
hit trial: 3000000
hit trial: 3500000
new max: 195 on trial: 3563925
hit trial: 4000000
hit trial: 4500000
hit trial: 5000000
hit trial: 5500000
hit trial: 6000000
new max: 198 on trial: 6005659
hit trial: 6500000
new low: 46 on trial: 6614767
hit trial: 7000000
hit trial: 7500000
hit trial: 8000000
new low: 45 on trial: 8015142
new max: 200 on trial: 8333263
hit trial: 8500000
hit trial: 9000000
hit trial: 9500000
hit trial: 10000000
</code>
Comment: @nitsua60 I was planning to just sell the rares. You know how many planeswalkers you get opening 100,000,000 BOXES of magic cards?
Comment: Oh man, on my 80 millionth trial (or so) it took 220 packs. Yikes!
Comment: Wow, that's a details rundown.  Thanks for doing that work. I dont think I would invest in 3 boxes to get commons. Again thanks for the rundown.
Comment: @nitsua60 In 39% of cases I bought two boxes (72 packs) and I had my entire play set. In the other 61% I had to go back to the store to buy a third box. 2% of the time, I had to go and get a fourth box, but very rarely did I have to buy a fifth. I mean, if I was a person buying stuff instead of a computer simulation.
Comment: Yanno, on second read it makes perfectly good sense. I don't know why I was getting twisted up last time I read it. In an case, be sure you recycle those hundreds of millions of wrappers! =D
Comment: No, I don't--because I haven't played since... Fallen Empires? Legends? (Don't quite remember their order, or if there was another around there.) Which is why I particularly enjoyed someone's comment about "way back in [names three systems I've never heard of] I did this...." =D
Comment: Can you post (or link) the implementation of the sim?
Comment: I'll try to remember the next time I'm on that machine, Caleth. Remind me like... tomorrow? :-)
Answer: Someone else might be able to do the math a bit better than me, but I will try to break it down for you. For this example lets use the recently released Hour of Devestation set.
Each Booster box you get will contain 36 packs.
Each Pack will normally contain 10 Commons, 3 Uncommons, 1 Rare, 1 Land.
However if you get a foil card it will take the place of one of your commons, so you may only get 9 Commons in a pack.
So one box of Magic cards will get you a bit less than 360 Commons.
In Hour of Devastation, there are 74 Commons not including Basic lands (so a full play set of Commons is 74 x 4 for 296 total cards). Since the cards you get from the packs are random it is unlikely (though I guess technically possible) for you to get a full play set of Commons from a single box.
Note: I really have no idea how to do probability calculations, so anyone who does feel free post an answer with the actual precentage chances. I am kind of intrigued by this now.
However, if you are willing to trade in your cards at your Local Game Shop, you should be able to swap any Rares or Uncommons you don't want for the Commons you are missing. As of writing the Commons in Hour of Devestation are between $0.16 and $0.11 a piece. Where as the Rares range from ~$7 to $0.30 (which you will have around 36 of) are and the Uncommonsrange from ~$2 to $0.15 (which you will have around 108 of). So you shouldn't have an issue converting any of the value you do get into a complete playset.
As a complete aside, if you do plan on doing this I would recommend getting some sort of binder or card box. There are a lot of cards in a booster box (550+ per box with tokens), and it can get pretty unwieldy pretty quick.
Comment: Thanks.  I was more looking for experience not an exact mathematical.  Figured there would be people on here that crack boxes and just wondering more how things tend to work out for them.  My guess is your right with thethe randomness a full pkayset of commons is unlikely. Might end up with 10 of one and 1-2 of another or something like that.
Comment: @jeffwllms That is possible to get 10 of one and none of another, but I don't think it is that likely. In my experience cracking boxes, there might be a couple commons that you get 5-6 of but you usually get at least 1 or two of each common. It really depends on how big the set is though, since every set is different. If you want a full play set of commons SocioMatt's answer is cheapest, but I find opening boxes to be fun and you may luck out and get an mythic rare that is useful for commander.
Comment: thanks packs are fun to bust open and it is nice to possible get some EDH bonuses.
Answer: Many e-tailers sell preorder and post-release packs of common playsets, which will guarantee you the full playset. Coolstuffinc has a pack that you can preorder for $19.99 that includes a full playset of commons (link is for Ixalan). You can also do this through ebay vendors both before and after set release (link is for Hour of Devastation).
This solution also prevents you from having to spend a lot of time selling extra cards you don't want. Additionally, sometimes you won't make back your initial cost anyway, depending on set value and the rares you open. A listing of all expected box values can be found at mtg.dawnglare.com. If you look at Hour of Devastation, assuming you don't get an invocation, the expected value is just over $83. If you buy a box at $110 from your LGS, you probably aren't making that back by trading in cards you don't plan to use.
You best solution is probably to just buy the playset outright, and buy any uncommon or rare cards you want as singles.
Comment: @scociomatt thanks for the info.  I always came across the common/uncommon sets.  And sometime after shipping you get up to getting within $30 or so of a box.  My reasoning for the question was more if there is a good chance of getting close to the same with the box the extra value for cards may be worth it.  Many say booster boxes are worth it because you get a bunch of bulk of no value. But for those wanting to just do pauper there is a some value there.   Anyway, thanks for the info and the links.
Answer: The probability of getting 4 copies of each common is effectively 0.
Taking @Malco's numbers of 360 commons in a booster box and 74 commons in a set, I believe the probability can be computed as:
360 Choose 292 * (73/74)^4 * (72/74)^4 * ... (1/74)^4
(You are guaranteed to get 4 of one common, so it's not counted in the formula, so there are only 292 cards that you are trying to open).
The product of this is 2*10^-49, which is to say 0.  Even though 360 Choose 292 = 3*10^74, the sum of fractions is around 10^-123.
That said, you will probably get pretty close to a complete playset, and can fairly easily trade or sell the rares to get the rest of the way.
Comment: There is an important piece of information, though. Each set of 10 is composed of a limited number of runs of 5. Thus you get 72 sets of 5 cards, and each of those sets is guaranteed to be unique. They are further guaranteed that no two sets that contain the same cards are going to be in the same pack (because packs are guaranteed unique). Exactly how much this changes the math, I don't know.
Comment: @corsiKa Well, that makes the math impractically more complicated.  If I had to estimate, I would say that gets you up to about 10^-30 or 10^-20.  It's still effectively 0.  I see you went the route of answering how many packs does it take rather than what is the probability for a given number of packs.

Where are you getting the details about the runs?  I'd be curious to see more about their structure
Answer: There are many online shops that have bulk deals. Star City Games the shop I usually buy from has for 20$US the gold collection with the following.

865 commons/uncommons
25 rares
25 foil commons/uncommons
5 foil rares
80 basic lands

If you want to get into pauper that would probably be a much better idea than buying maybe 6-8 packs for the same money. I have only bought their rare lots but they are not charlatans. They don't actively try and con you, they are not above putting some casual goodness in their lots.
(PS Unaffiliated)
Answer: OP asked for anecdotal evidence in one of the comments.
Back in the day (Tempest, Exodus, etc.) I generally had to buy 2 boxes of boosters to get a complete play set of commons (i.e. 4 of each).
Comment: Thanks.  From what I am taking from the people trying to do the math that kinds of sounds right.
Comment: "Back in the day" however there was almost no math to it at all because cards were printed and packs packed and boxes loaded in a fixed order. :)


What is the difference between layout and design?

Question: I can't understand what is "design" and what is "layout" in terms of web design. I'm confused between layout and design. Can anybody can help me understand these matters? Thanks for reading my question.
Answer: They are really closely related.
Layout is defined as the arrangement of predetermined items on a page. Basically, you're given the pieces and they are arranged.
Design is defined as the art or skill of combining text, images, and other items into a visually pleasing arrangement.
So, really they can be almost interchangeable.
The primary difference is that for layout you don't need to create anything. You just decide on placement, color, size, etc for items you already have. You don't pick typefaces, or color themes, or any of the "overall" visual aspects. Layout requires you to fit content into a specified theme or schematic.
For design you typically create things or find things to use. Such as, you draw a series of icons to use in the layout. Or you find stock photos and edit them to fit your layout. Design is also where global decisions are made - such as which typefaces will be used, the overall color theme, number of columns, trim size, bindery necessary (if any), etc.
Most graphic design (web or print) encompasses layout. However, a layout does not necessarily encompass any design.
It's a fine line and this is really just my opinion. There are few, if any, hard rules on what constitutes layout vs design. They both take a skilled eye when dealing with things like balance, proximity, space, etc.

-- To use an analogy: If baking cookies. Layout is putting the ingredients together, mixing them, and baking them. Design is deciding what ingredients are needed and what type of cookie you want to make, how many cookies, how long they should be baked at what temperature, etc.
Comment: Also, the layout and design are almost always made by the same person, they are part of a single process so it's really hard to draw a line where the layout ends and designing starts...
Comment: Five years later you come back with a cookie analogy!  Are you hungry? What is *eating* cookies an analogy for?
Comment: I edited more than just that @Wolff `:)` I suppose I could have used a mechanic vs auto manufacturer as an example. But who doesn't like cookies? (and only edited because I saw the new answer today - I didn't bump it.)
Comment: I don't care if you bump your answers as long as you add food analogies.
Comment: @Wolff .. made.. of.. erm... puppy dog toes?
Comment: It's a [cookie](https://duckduckgo.com/?q=%F0%9F%8D%AA)!
Comment: I don't agree it's "often the same person". At our office we have a lot of standard book *designs* for clients to choose from, and if they pick one, any of our studio people can do the *layout* using that design. Only when a custom job is asked for, it's best to leave it to one single person – and then mainly because it's easier to communicate and fine-tune with the client.
Comment: (Even then: our processes are flexible yet standardized. When necessary, if the design is agreed upon, someone else can take over the brunt of the work of the layout.)
Comment: In order to *design*, one **must** also do a *layout*.. at least once.
Comment: @Scott: yes `:)` but deciding the layout is part of the design process.
Answer: When used distinctly, layout refers to spatial distribution of components: you just need the components' dimension and (absolute) position in the page to build a layout. In this case of use, design encompasses layout and rest of questions related to desired display.
Answer: Another way to think about this.
A news paper is designed, including choosing type face, column widths, colours for heating etc to get the "house style".
Then each day a layout is done with today's news and photos.   The layout is done keeping to the rules that were decided at the time of the design.   Layout can include rewriting a headline so it fits in better or cropping a photo, but is unlikely to include choosing the typeface.
Answer: a lot depends on how you use the term "design". design refers to the overall project which a part of is the layout. the layout elements must then also be individually designed to fit and compliment the overall design. I am a landscape architect, and have to design in 3D as well as graphically.my plans can be compared to a website in that I have to convey a lot of information visually and in clear, orderly yet pleasing visual experience. the way I see it; overall design incorporates  the layout which incorporates individually designed elements.
Answer: Layout is the placement or the arrangement of all the elements while the Design serves as the plan or the visual presentation/appearance of the layout.
Answer: Design is the theoretical planning of each page,.
Comment: And what is *layout* then?
Comment: Objective a good printer materials design is important,  because part of the selling a publication.
Answer: Design= Layout & Style.
Layout= Pure Objects Arrangement In Space.
style= The Types Properties Of The Objects.


What is ADS-B and who needs it?

Question: I read that ADS-B is required by the year 2020. What does this mean? What is ADS-B used for, and who needs it?
Answer: To answer your first question, ADS-B stands for Automatic Dependent Surveillance - Broadcast.

Automatic in the sense that it operates without external stimulus (unlike radar)
Dependent in the sense that the surveillance information is derived from on board systems
Surveillance in the sense that it's primary intended to provide surveillance information to other parties
Broadcast because it transmits to all listeners without knowing who those listeners are, there is no two-way communication.

The capability of an aircraft to transmit ADS-B signals is called ADS-B OUT, the capability of an aircraft to receive ADS-B signals is called ADS-B IN.
ADS-B data contains information about the identity, position, altitude and velocity of the aircraft. The position and velocity information is derived from GNSS (GPS).
There are three technologies defined for ADS-B

1090ES is operating on 1090 MHz, the same frequency used for Secondary Surveillance Radar (SSR) and Airborne Collision Avoidance Systems (ACAS/TCAS). Messages are transmitted by the same transponder that also replies to radar interrogations. This will be a Mode-S capable transponder because the data is formatted in a similar way. Since this frequency is the worldwide used standard for aviation, international aviation will use this ADS-B standard.
UAT (Universal Access Transceiver) works on 978 MHz. A special transceiver is required to use this form of ADS-B. The transceiver is able to send and receive data, it will also receive ADS-B transmissions from other aircraft. UAT is only allowed within the USA and China. The frequency 978 MHz is reserved for other purposes (DME/TACAN) in other countries.  To encourage people to equip with ADS-B voluntarily, the FAA provides additional services on UAT. These are Traffic Information Service - Broadcast (TIS-B) which transmits position of aircraft detected by FAA's SSR's and Flight Information Service - Broadcast (FIS-B) which provides the receiver with weather information and operational data such a airspace restrictions and NOTAMS.
VHF Datalink Mode 4 (VLDm4) uses a frequency in the 118-136.975 MHz block, which is internationally reserved for aviation. Normally these frequencies are used for voice communications, so a special radio is required to support VDLm4. Just like UAT, VDL mode 4 allows for services like TIS-B and FIS-B. VDLm4 was tried in Sweden and Russia, but has not been able to gather much mass. It is unlikely that it will be used on a large scale.

Since you mention 2020 as the year by which aircraft should be equipped with ADS-B I am going to assume you are from FAA-land.
The FAA mandates aircraft in the 48 contiguous states (and D.C.) that operate in class A, B, or C airspace or class E airspace above 10000ft (class E airspace below 2500 AGL excluded) to be ADS-B OUT equipped by January 1st, 2020.
The mandate itself can be found here and the associated Advisory Circular (AC90-114) can be found here.
Aircraft operating below 18000 ft can use either UAT or 1090ES. Above 18000ft, 1090ES is to only approved ADS-B technology.

Countries that have ADS-B mandates are (this list is probably not exhaustive)

Australia
Canada
(Hudson bay)
China
Countries in the European Union
Fiji
Hong Kong
India
Indonesia
Seychelles
Singapore
USA
Vietnam
Comment: I believe that the EU is requiring this next year isn't it?
Comment: @Lnafziger yes, but not for all aircraft. Politics and lobbying have complicated the rule. And it might be even subject to change.
Comment: Maybe the reference to the logic behind the terms could be added. I think dependent also means that, for ADS-B concept to function, there should be good-hearted willing-parties that broadcast their location at all times. and i case of a system failure other backup methods (systems or procedures) should be available.
Comment: @GürkanÇetin The term cooperative surveillance is used for what you describe. ADS-B is a form of co-operative surveillance, just as secondary radar and multilateration.
Comment: I don't believe Canada is mandating ADS-B. The most recent information I could find is from 2011-03-11 https://www.tc.gc.ca/eng/civilaviation/opssvs/managementservices-referencecentre-acs-700-700-009-130.htm#s3_0 saying that it isn't being mandated
Comment: @mark, ADS-B is mandated for operations over the Hudson bay.
Answer: ADS-B is a complex topic, but the FAA has mandated that by 2020 most aircraft operating in any airspace that currently requires a Mode C transponder should be "ADS-B Out" equipped, with minor exceptions.
Notice that it is possible to be "ADS-B In" equipped but not "ADS-B Out" equipped.  The FAA does not mandate anything regarding "ADS-B In" yet.
There are various safety and efficiency benefits of having ADS-B equipped aircraft.  ATC benefits from ADS-B Out by having more accurate position information, allowing them to potentially allow aircraft to operate closer to each other since current radar technology is far less accurate.  Pilots benefit from ADS-B In by being able to receive weather in the cockpit and see the depicted positions of aircraft around them for collision avoidance.
Answer: This MIT paper is a bit dated, but very technical information about the ADS-B protocol for the tinkerer in you.

What is ADS-B and who needs it?


How to share a Facebook application post with friends

Question: Bob, Mary and Jane are Facebook users. MyApp is a Facebook Application.
Bob and Mary are friends. Mary and Jane are friends. Bob and Jane are not friends.
Bob is a user of MyApp (installed, publish_stream).
MyApp publishes a post to Bob's stream, using the Graph API Post (scroll to "Publishing").
Mary "likes" or "comments" on the post.
Problem: Jane cannot see Mary's "like" or "comment" (she would be able to see a "like" by Mary of Bob's status).

I cannot, for the life of me figure out how to create a Post that can be shared further. I tried changing the privacy field to FRIENDS_OF_FRIENDS , EVERYBODY, etc.
Alternately, any suggestions on how to include or write a "share" action link would be welcome!
Answer: I don't believe that what you're trying to do is possible.


How to hide the armature to do UV unwrapping?

Question: I'm new to Blender. I have made and rigged a character and want to do UV unwrapping to texture it but I don't know how to hide the armature to be able to do the next step. Please advise.
Answer: You could use one of two approaches to do this.

Layers
Object Hiding

Layers
This is what I would recommend.
Layers let you control at what level an object is "visible" much like a layer in a program like photoshop. You can enable or disable layers and move objects to different layers. To move an object to another layer you only have to use the M key by default
Simply select your Armature object(s) and hit M then you can move to any of the layers you want. The little orange dot in the layer selector shows which layer the active object is on.
You can read more about layers here and since you might be new, it is very good to understand how they make working with blender easier.
Object Hiding
If for some reason you cannot use layers, you can hide the objects you do not want to see while not moving them to another layer. You can do this by selecting the object(s) you want to hide and pressing H.
Once this is done you can no longer see / select the object from the 3d view. The object will still show up in renders.
If you want to see all the objects you have hidden, you can press Alt + H.
If you only want to unhide specific objects, you can use the outliner (the tree view in the top right) and click on the eye icon to unhide hidden objects.
You can also use other shortcuts to hide objects en masse etc. This post also details one way you can hide all objects EXCEPT the selected object
Comments:
You can use both object hiding and layers together but turning off a layer makes it get hidden from rendering.
Hiding an object but keeping its layer visible does not make hide it from rendering.
Answer: Click the Eye icon just to the right of your Armature in the Outliner Window.
The other icons are an arrow next to the Eye that enables and disables selecting an object, and the Camera decides if an object is shown in the render window.
Answer: You could select all the bones , move them to a new layer and hide that layer


The Puzzle of the mitzvah to be Samach Chosson Vikallah

Question: There is a Mitzvah to make the Chosson (groom) and Kallah (bride) happy on the day of their wedding. This Mitzvah is of utmost importance as it is one of the few Mitzvos for which we stop learning torah (another one would be attending funerals).This illustrates the importance of this category of Mitzvos. The question is why on such a stand-alone happy day? After all, the couple is getting married. Is there a requirement for the guests to make them more happy?
Comment: `as it is one of the few Mitzvos for which we stop learning torah` Actually one stops learning Torah to perform any mitsvah that will not be performed by others.
Answer: To understand why we make the couple happy, we must first point out the way we make them happy, which is by praising them. As the gemara in Kesuvos 17 asks 'how do we dance before the bride? By saying she is attractive and kind'.
The reason to praise the bride and groom is so they should be happy with their decision to get married. As Beis Hillel ends the discussion there by saying 'when someone buys something in the market, should you praise itin his eyes, or degenerate it?'. So the basic idea is that at the time when someone makes the most life altering decision they will ever make, we try to help them be happy with their decision, and not be nervous about it, or have regrets. This is most applicable right away at the wedding and the seven days of feasting.
By praising and entertaining them, they ignore their nervous feelings.
In fact, the Radal on Pirkei DeRabi Eliezer chapter 16 #61, points out just how deeply this praising of the couple is connected to praising someone's acquisition. He points out that the gemara in Kesuvos 17a only mentions praising the bride, whereas the Pirkei DiRabi Eliezer mentions praising the groom as well. He explains that the sugya in Ksuvos was discussing whether to praise her with her actual qualities or give a standardized praise was specifically taking into account the fact that the groom was the one who made the kinyan, aquirement, therefore Beis Hillel argued to Beis Shamai that a standardized praise was in order, just in case she is lacking qualities, we don't want him to regret his aquirement.
But, says the Radal, concerning the praise about the groom, Beis Hillel will agree with Beis Shamai to praise him with his actual qualities, because a woman is happy with anything, as we see in Kedushin 41a טב למיתב טן דו.
Comment: you said over a radal but did not answer the question they are already happy why add the command


Is it possible for web crawlers to see static pages without following a link to them?

Question: If I create a static page on a domain (http://www.domain.com/page.html), can a crawler still see it if there aren't any links to it anywhere on the site?
Comment: Yes, just send the link in [Skype and Bing will find it and index it for you](http://arstechnica.com/security/2013/05/think-your-skype-messages-get-end-to-end-encryption-think-again/).
Answer: Can they see it? Yes. Can they find it? Not without help.
Web crawlers typically find pages to crawl by following links to them on other pages. Some crawlers (e.g. search engine crawlers) will also crawl pages listed in special XML files. So if there is no link to page on your website or any other website then that page will not be crawled (pages that contain the URL of that page but are in plain text will be found by Google).
However, once a page is found and crawled it may be crawled again even if all links to that page are removed from their respective websites. This is because pages that are crawled are then indexed (e.g. added to the crawlers list of pages to crawl again) so the crawler knows to crawl it again at a later time to look for changes. If you want to prevent this from happening you can do any of the following:
Most effective

Remove the page from the Internet
Changed the URL of that page (essentially removing the page and adding a new one)
Place it behind a login

Less effective

Block that page using a robots.txt file (which may be ignored)
Try to filter out bad bots by IP (which can change with every visit) or user-agent (may be spoofed)
Answer: Another way the page may be discovered is when you have links to other sites on that page.
The URL of you page will appear in their referrer logs, a nice time-pass of many webmasters is to briefly browse through those logs and see what others are saying about their pages.
Some sites seem to provide access to those logs without any access restriction, thus crawlers can reach them too...
To keep the page really secret, don't let it link out to external sites.


What came before web services and SOA?

Question: I'm interested in the history of distributed, collaborative, cross-organisational programming paradigms - web services and SOA are de-facto now, but what came before? What models have been superceded by SOA?
Thanks
Comment: SOA and web-services are two completely different things. SOA is more of a methodology while web-services are standards.
Comment: They may be completely different things - but they're also complementary and enabling technologies, SOA is built on the standards layed down by web services. Me thinks you're being a little pedantic :)
Comment: he's not being pedantic. There are web services that don't care about SOA, and SOA embraces things other than "web services".
Answer: Well, I suppose there was RPC - which is really what SOAP is, only they didn't piggy-back the data payload on top of a standard protocol (http in SOAP's case). So CORBA and DCE-RPC and ONC RPC  all did the same thing, but only over internal networks, not over the internet.
There was also EDI as a 'standard' for exchanging data between disparate entities. This was effectively a way of defining what the data payload would look like (similar the the XML part of SOAP).
But these are still not SOAs really, they provide the same functionality but the big difference was how people thought of using them. Once you could write a machine-to-machine 'website' and have different machines talk to each other through them, it took off. You could do it before using CORBA, say, but it wasn't as easy or as widely known about. You can tell this has happened by the fact we have several terms used for effectively the same thing - SOA, SaaS, Web Services... all the same thing (but lots of money to be made 'consulting' on the difference ;) )
Answer: I don't really think you'll find anything that's been superceded by SOA.  You will find that there's been progress in organizing computer programs to take advantage of the SOA type principles.  As for programming models that have been in reasonably common use, well, let's see... CORBA, RPC, more generic client-server applications.  Of course, computer-to-computer communications were preceded by process-to-process communication using a wide variety of conventions.
SOA as a philosophy of breaking large problems into smaller ones and then composing the results has been known and applied since humans started making bricks instead of building complete walls.  Of course, that was mostly implicit.  Explicit statements for SOA really started to come about with CORBA and, while SOA is independent of Web Services, the advent of HTTP and XML, and then SOAP, really started to make development of non-specialized "services" easier, more worthwhile and thus common.
Answer: Maybe Silos?
...where services are just not shared across an enterprise, at least in a standard way.  This is why products like BizTalk are used: to get silos to talk to each other via standard interfaces.
Answer: This pdf A Note on Distributed Computing should be an interesting read. It is pre-SOA and would give an idea of the history up to that point (1994).
I would say distributed object technology. And before it remote procedure calls.
RPC is one of the earlier approaches and gained popularity from the Sun implementation. One of the famous uses is NFS (network file system).
As object oriented programming became more popular, distributed objects followed. Most important was Microsoft DCOM (and later COM+) and, more industry wide, CORBA.
SOA is a divide and conquer approach that is critically dependent on the concept of services. Which is different from objects as used by CORBA et al, as well as being different from resources as in REST.
Objects are created and their lifetime is typically controlled by the client. On the other hand, services are assumed to be always there provided by the server. This is one reason why SOA is not equivalent to distributed objects.
Services are also stateless, which means that the server when considering the response to a service request need not look at the history of interaction with the client. This was not a consideration when originally devising the RPC concept as scalability wasn't such an important issue then. Interestingly, large scale users of RPC did notice the relationship between scalability and statelessness. The NFS RFC explicitly mentions stateless servers, though with reliability as the main concern. Anyway, statelessness is one of the main difference between services and plain old RPC.
In short, no. I don't believe in the revisionist history of SOA being since the dawn of time. Any more than the universe being written in Lisp (or Perl for that matter). Nor is it equivalent to divide and conquer or division of labour.
SOA started as a concept at some point in the nineties. Overlapping with the development of CORBA. It is much harder to pinpoint an actual date or event and there are more than a few claims to the conceptualisation of it.

What came before web services and SOA?