Why are plane lights dimmed before landing at night?
Why is the light in an airplane turned off during take off and landing?
Previous question:    That was when my buttons died.  On other days, my text dies.    And some times it's just italics.    Now, I like blaming @skiwi for this, and he's often nearby when it happens.  But today, he's not here, and it happened again.    I'm running Windows 8 and using Chrome 40.0.2214.94 m.  Refreshing and such does not fix the issue.  Inspect element -> console -> error log:  http://chat.stackexchange.com/chats/8595/messages/new Failed to load resource: the server responded with a status of 409 (Conflict) http://i.stack.imgur.com/2ZJdJ.png?s=128&amp;g=1&amp;g&amp;s=16 Failed to load resource: the server responded with a status of 502 (Bad Gateway) http://i.stack.imgur.com/boUZp.jpg?g&amp;s=16 Failed to load resource: the server responded with a status of 502 (Bad Gateway) http://i.stack.imgur.com/U8P3C.jpg?s=128&amp;g=1&amp;g&amp;s=32 Failed to load resource: the server responded with a status of 502 (Bad Gateway) http://i.stack.imgur.com/boUZp.jpg?g&amp;s=16 Failed to load resource: the server responded with a status of 504 (Gateway Time-out) http://chat.stackexchange.com/messages/19891816 Failed to load resource: the server responded with a status of 409 (Conflict)   What's going on here?  I should note, I can view italics by selecting, then alt-tabbing:    So it reeks of a client-side issue. What's hiding the text from me?  EDIT:  30 april 2015 it happened again =/ How do I find out which process is locking a file using .NET? Where and why do I have to put the "template" and "typename" keywords? The Chinese government has a really specific list of requirements for visa photos:    I had an old unused photo from last time I applied for a visa or passport, and compared it to the requirements (decided not to use it because it was damaged). It seemed to match most of the requirements, except that it seems that they want a photo which isn't square: The required width is less than the required height.  Assuming most drugstores are still providing square passport photos, the question becomes: Should I cut the photo to match the specified width?   What adds to the confusion is if you look at the  the box for the photo is nearly square, not the oblong shape in the requirements. And I have seen other advice that you need to make sure it fully fits the box.  Any advice about what to do here? What methods of ‘clearfix’ can I use? I have the age-old problem of a div wrapping a two-column layout. My sidebar is floated, so my container div fails to wrap the content and sidebar.  &lt;div id="container"&gt;   &lt;div id="content"&gt;&lt;/div&gt;   &lt;div id="sidebar"&gt;&lt;/div&gt; &lt;/div&gt;   There seem to be numerous methods of fixing the clear bug in Firefox:   &lt;br clear="all"/&gt; overflow:auto overflow:hidden   In my situation, the only one that seems to work correctly is the &lt;br clear="all"/&gt; solution, which is a little bit scruffy. overflow:auto gives me nasty scrollbars, and overflow:hidden must surely have side effects. Also, IE7 apparently shouldn't suffer from this problem due to its incorrect behaviour, but in my situation it's suffering the same as Firefox.  Which method currently available to us is the most robust? Removing all 'stable' theme's CSS from a Drupal 8 custom theme I would like to remove all CSSs automatically included from stable theme:  /core/themes/stable/css/system/components/*   I can remove them one by one inside the .info.yml file:  stylesheets-remove:   - 'core/themes/stable/css/system/components/ajax-progress.module.css'   - 'core/themes/stable/css/system/components/autocomplete-loading.module.css'   - ...   Is there a way to remove all of them at once?   Something like:  stylesheets-remove:   - 'core/themes/stable/css/system/components/*' Expected Value of Max of IID Variables What is the expected value of the maximum of 500 IID random variables   with uniform distribution between 0 and 1?   I'm not quite sure of the technique to go about solving something like this. Could anyone point me the right direction?  Thanks Why won't Mathematica display an answer? What is the difference between "information on", "information of", "information about" "Information on something", "information of something", "information about something" — these three usages all sound having the same meaning for me. Are there any differences? Are the "umbles" etymologically related? From      And we show telltale signs of early hypothermia, what the doctor and   the National Institutes of Health and other cold-weather cognescenti   call the "umbles."      First we lose some fine motor skills, McLaren says, "and we start to   fumble. And tumble. And stumble."      Then our cognitive abilities are compromised. "We mumble and we   grumble."   Are the "umbles", such as fumble, tumble, stumble, mumble and grumble, etymologically linked, either in terms of sharing a common ending, or entire words having a common ancestor?  Trying to do a search of the etymology of the umbles ended up giving the etymology of the word  instead. I'm rather interested in getting my feet wet at the interface of  and . Can anybody give me references to some good books on these topics? I'm looking for very introductory technical books. Request Web Page in c# spoofing the Host I need to create a request for a web page delivered to our web sites, but I need to be able to set the host header information too.  I have tried this using HttpWebRequest, but the Header information is read only (Or at least the Host part of it is).  I need to do this because we want to perform the initial request for a page before the user can.  We have 10 web server which are load balanced, so we need to request the file from each of the web servers.    I have tried the following:  HttpWebRequest request = (HttpWebRequest)WebRequest.Create("http://192.168.1.5/filename.htm"); request.Headers.Set("Host", "www.mywebsite.com"); WebResponse response = request.GetResponse();   Obviously this does not work, as I can't update the header, and I don't know if this is indeed the right way to do it. What is $1^k+2^k+\cdots+ (p-1)^k$ modulo $p$? (From Ireland and Rosen). I've been working through a bit of Ireland and Rosen's Number Theory for fun. Problem 4.11 of Ireland and Rosen asks     Prove that $1^k+2^k+\cdots+(p-1)^k\equiv 0\pmod{p}$ if $p-1\nmid k$, and $-1\pmod{p}$ if $p-1\mid k$.    My work is leading where I didn't expect to go. Here I assume $p$ id odd. First, if $p-1\mid k$, then we can wrike $k=(p-1)j$ for some $j$. But then $$ 1^k+\cdots+(p-1)^k\equiv 1^{(p-1)j}+\cdots+(p-1)^{(p-1)j}\equiv \underbrace{1+\cdots+1}_{p-1\text{ times}}=\frac{(p-1)p}{2}\equiv 0\pmod{p} $$ since $p-1$ is even.   Secondly, I suppose $p-1\nmid k$. WLOG, I can assume $0&lt;k&lt;p-1$, Since if $k=(p-1)j+r$ with $0&lt;r&lt;p-1$, then  $$ a^k\equiv a^{(p-1)j+r}\equiv a^r\pmod{p}. $$  Then if $g$ is a primitive root, $$ 1^k+\cdots+(p-1)^k=\sum_{i=1}^{p-1}(g^k)^i=\frac{g^k(1-g^{k(p-1)})}{1-g^k}. $$ Since $g$ is primitive, $p\nmid 1-g^k$, but $p\mid 1-g^{k(p-1)}$, so the above sum is again congruent to $0\pmod{p}$.  So in all cases, I get the sum is congruent to $0$ regardless. Have I messed up, or is there a typo? Thanks. How does the new Tie-Breaker work? In Clash of Clans there was an update on 9/16 adding a Tie-breaker into the wars, can anybody explain in detail how this mechanism works? Alternative of `route -n` of Linux in Mac How can I see the list of routes and its corresponding gateway in a Mac ? The command in linux is route -n .  For a particular IP address, I am able to get the routes for an particular IP address via route get 10.0.0.0. On freedom in Sartre's existentialism I am reading "Existenstialism is a humanism", the text of the famous conference by Sartre in which he explains his own version of existentialism. I think is full of logical inconsistencies, but maybe it's just because I don't understand it or I don't know enough about existentialism. Anyway, my question is about a specific passage. After having "demonstrated" that there is no way one can derive an ethics outside of Man (God does not exist and reason is insufficient), he asks himself according to what principle a person should behave and he says:     "For I declare that freedom, in respect of concrete circumstances, can   have no other end and aim but itself; and when once a man has seen   that values depend upon himself, in that state of forsakenness he can   will only one thing, and that is freedom as the foundation of all   values. That does not mean that he wills it in the abstract: it simply   means that the actions of men of good faith have, as their ultimate   significance, the quest of freedom itself as such."   So it seems Sartre says that when deciding a course of action, people will always choose "freedom," (and also, elsewhere, that "freedom" is always a good thing). That is for him the only principle, the only moral that governs or should (because we can do wrong judgments about what is freedom) govern our action.  My questions are:  1) do I understand correctly Sartre's thinking?  2) He says: a) freedom is absolute; b) the values that man chooses are also absolute because no God or reason can tell him what to do, c) therefore man will choose freedom. Is there any logic in this statement? If I replace freedom with X where X is "pleasure" or "justice" or "pain" or "zero temperature", wouldn't I "demonstrate" by this logic that man will choose X?  3) assuming what I said makes any sense, how can existentialism ever find a rule of moral conduct? and if it does, what is it and how can be demonstrated? and if it cannot, why is or has been important at all as a philosophy?  Thanks! To select a child node in jQuery one can use children() but also find().   For example:  $(this).children('.foo');  gives the same result as:  $(this).find('.foo');  Now, which option is fastest or preferred and why? Ambiguity of "quite" I have researched and found out long time no see is a direct translate from the Chinese phrase, 好久不见. As much as we use it almost everyday in our lives, is it actually grammatically correct? Since it is a direct translate, is it grammatically approved? Why PlotStyle->Dashed make everything dashed?