When referring to flash exposure, what does "max sync speed" mean?
What exactly is flash sync speed and should it be a factor in a buying decision?
Optimizing logical sector size for physical sector size 4096 HDD Add an image directly from the clipboard I've tried to find other questions covering this, but (surprisingly) I did not find any.  When I want to add a screenshot to a post, as far I know the only way to do it is to save it as a file and then upload the file, using Stack Overflow's image hosting. OK, much better than finding a hosting site yourself, but sometimes I wish I could just paste the image from the clipboard.  It's not as straightforward as it may seem, I know. , and it needs a Java applet to get it done. Improving upon ArcGIS Buffer/Dissolve performance? LINQ to read XML I got this XML file:  &lt;root&gt;     &lt;level1 name="A"&gt;         &lt;level2 name="A1" /&gt;         &lt;level2 name="A2" /&gt;     &lt;/level1&gt;     &lt;level1 name="B"&gt;         &lt;level2 name="B1" /&gt;         &lt;level2 name="B2" /&gt;     &lt;/level1&gt;     &lt;level1 name="C" /&gt; &lt;/root&gt;   Could someone give me a C# code using LINQ, the simplest way to print this result: (Note the extra space if it is a level2 node)  A   A1   A2 B   B1   B2 C   Currently I got this code:  XDocument xdoc = XDocument.Load("data.xml")); var lv1s = from lv1 in xdoc.Descendants("level1")            select lv1.Attribute("name").Value;  foreach (var lv1 in lv1s) {     result.AppendLine(lv1);      var lv2s = from lv2 in xdoc...??? } Is there any method to close connection similar to  for  in WordPress?  Is it not necessary to close connection for global $wpdb? Error: j_id0:j_id1:j_id28:j_id30: Validation Error: Value is required I've installed reCAPTCHA module but spam still bypass my security and leave nasty comments. What should I do? How to block them? Last night, I was using Chrome just nicely, but this morning, I can't even start Google Chrome as it immediately crashes. I have already tried a clean uninstall and reinstall of Google Chrome but still the same error pops up (it does not happen while I'm opening Google Chrome. I woke up and only then realized I can't open my Chrome and it keeps popping up saying that Google Chrome has stopped working.)  OS : Win 7 64-bit  Here is the detail of the crashes  Problem signature:  Problem Event Name:    APPCRASH   Application Name:    chrome.exe    Application Version:    35.0.1916.114 Application Timestamp:    53726019    Fault Module Name:    chrome.dll   Fault Module Version:    35.0.1916.114   Fault Module Timestamp:    53725d18    Exception Code:    c0000005    Exception Offset:    00728bc8      OS Version:    6.1.7600.2.0.0.768.3    Locale ID:    17417    Additional Information 1:    0a9e    Additional Information 2:    0a9e372d3b4ad19135b953a78882e789    Additional Information 3:    0a9e    Additional Information 4:    0a9e372d3b4ad19135b953a78882e789     Any help that will solve this problems is greatly appreciated. Black screen after installation of Ubuntu 18.04 I was able to star my own message by pinning it and unpinning it.  Pinning a message adds a star, even to your own messages, but when the pin is removed, the star remains. Fantasy/scifi combo - band of travelers who must get from "sphere" or domain to domain - each geographic area is ruled by a magician - it turns out later these are people who are unwittingly tapping into the computer grid they all live on to alter their own reality? Mark questions to receive notifications and updates? Integer $x$ for which $x^4+x^3+x^2+x+1$ is perfect square. Integer values of $x$ for which $\bf{x^4+x^3+x^2+x+1}$ is a Perfect Square.  $\underline{\bf{My\; Try}}$:: Let $\bf{x^4+x^3+x^2+x+1 = k^2}$, where $k\in \mathbb{Z}$  $4x^4+4x^3+4x^2+4x+1 = 4k^2 = (2k)^2$  Now How can I proceed after that  Help Required,  Thanks "Like" versus "as" My "network reputation" graph does not accurately reflect my accounts Code block is not properly formatted when placed immediately after a list item Consider the following piece of Markdown code:  This is some regular text.      &gt;&gt;&gt; def factorial(n):     ...     return 1 if n &lt; 2 else n * factorial(n - 1)     ...   * This is a list item.      &gt;&gt;&gt; def factorial(n):     ...     return 1 if n &lt; 2 else n * factorial(n - 1)     ...    Notice that the second code block is preceded by a list item.   Why is the factorial code not properly formatted under these circumstances? To demonstrate the problem, I'll insert the Markdown code show above:    This is some regular text.  &gt;&gt;&gt; def factorial(n): ...     return 1 if n &lt; 2 else n * factorial(n - 1) ...     This is a list item                 def factorial(n):       ...     return 1 if n &lt; 2 else n * factorial(n - 1)       ...               This applies to numbered as well as unnumbered lists. I have this struct:  struct Map {     public int Size;      public Map ( int size )     {         this.Size = size;     }      public override string ToString ( )     {         return String.Format ( "Size: {0}", this.Size );     } }   When using array, it works:  Map [ ] arr = new Map [ 4 ] {     new Map(10),     new Map(20),     new Map(30),     new Map(40)};  arr [ 2 ].Size = 0;   But when using List, it doesn't compile:  List&lt;Map&gt; list = new List&lt;Map&gt; ( ) {     new Map(10),     new Map(20),     new Map(30),     new Map(40)};  list [ 2 ].Size = 0;   Why? What happens if both players have the ability to pump their creature an unlimited number of times? Say that both players each had 2 , 2 , and a . (Or any other way to get unlimited mana, and a Nantuko Shade).  Player 1 attacks with his , and player 2 blocks with his . Before damage is assigned, each has chances to pump up their  as much as they want. They can't just declare them to be "infinite," but each can always one-up the other player. What happens?  It seems there would be a loop of events, but would one player eventually be forced to break the loop as per rule 714.3? Is it considered the same game state after each player pumps their creature a bunch as it was before?  This was discussed at length on the Draw3Cards Magic Q&amp;A site (which is no longer available), but no conclusion was reached. Some felt that the game would simply be a draw, others felt that the active player would be forced to make a different decision to break the loop. Others felt that you would just have to call a judge and see what he decides. Trouble plotting arctan with pgfplots I'm trying to plot arctan(x) with pgfplots but I don't get a good output. Here is my code:   \begin{cfigur}\begin{axis}[      width=160pt,compat=1.5.1,grid style={ultra thin},every axis plot post/.append style={thick},      x tick label style={font=\tiny},y tick label style={font=\tiny},      scale only axis,grid=major,axis lines=middle,      xlabel={$x$},      ylabel={$y$},      xmin=-200,      xmax=200,      domain=-200:210,      ymin=-5.5,      ymax=5.5,      xtick={-150,-100,...,150},      ytick={-5, -4,...,5},      restrict y to domain=-20:20,      legend style={at={(0.5,-0.05)},anchor=north,nodes={right}},  ]  \addplot[mark=none,color=blue, samples=500]{atan(x)};  \addlegendentry{$y = \tan^{-1}x $};  \end{axis}\end{cfigur} I just reached the 3k rep limit required for close votes and have started exploring the vote-to-close UI that's opened up to me, and I have a request.  The review queue has a Do Not Close button, but when I click the close link under a question that has close votes (i.e. it shows close (1)), there isn't an option for me to vote against closing the question. I came across a question that had a vote to close it as not a question, but it had just been updated with code and more details and was no longer a candidate for closing. However, I couldn't cast a vote to not close it from the question itself. When I clicked on close, it brought up the usual voting UI, and "Do Not Close" was not an option.  TL;DR, do this:   Open a question in the close votes review queue Note the Do Not Close button Click the question title to go to it Click the close (n) link under the question (assuming it hasn't already been closed) Notice the lack of an equivalent "Do Not Close" option   Could a "Do Not Close" option be added to the close button popup for questions that already have close votes, that way the review interface isn't the only place a "Do Not Close" vote can be cast?  Edit: Okay, so 5 3 "Do Not Close" votes kicks it out of the review queue, it doesn't have "no effect" as suggested in the comments. (See , in which the  was just updated a few minutes ago to say 3 DNC votes.) I still don't see why the same DNC option can't be available from the question.  Basically, I guess I would like some rationale behind this bullet point from :     Only accessible from the review queue (so rather difficult to target a specific question). Yes, this is very much by-design.