Why does it always say "Unable to connect" in Minecraft on Android?
Friend can't join world
If I left food out of the refrigerator for some period of time, is it still safe? If I left it out too long, can I salvage it by cooking it more? Sum with binomial coefficients: $\sum_{k=0}^{n}{2n\choose 2k}$ I'm repeating material for test and I came across the example that I can not do. How to calculate this sum: $\displaystyle\sum_{k=0}^{n}{2n\choose 2k}$? Could someone provide me with a good explanation of why $0^0=1$?  My train of thought:  $x&gt;0$  $0^x=0^{x-0}=0^x/0^0$, so  $0^0=0^x/0^x=\,?$  Possible answers:   $0^0\cdot0^x=1\cdot0^0$, so $0^0=1$ $0^0=0^x/0^x=0/0$, which is undefined   PS. I've read the  on mathforum.org, but it isn't clear to me. Longtable: page breaks within row possible? I am editing a longtable. Some of my cells contain a lot of text. Page breaks seem to happen only where table rows end/begin. I'd like, however, for the rows to span pages; it's fine with me if, for example, the first few lines of a row are at the end of one page and the rest of the row's lines are on the next page. Extracting embedded images from a PDF Trash icon and files have disappeared from the desktop after upgrade to Ubuntu 19.04 Noise in JPEG file after processing RAW file in photoshop Recently i started shooting in RAW after understanding its advantages over JPEG format.   While processing the RAW file there is an option to reduce noise in a captured picture. It works great when i am working on RAW file. But as soon as I save file in JPEG format, noise comes back.  I understand that while converting from RAW to JPEG compression techniques will be applied. But how can i handle this situation (while doing post processing)? Capitalisation of "Section" and "Chapter" in a Ph.D. Thesis I am submitting a Ph.D. thesis fairly soon and my supervisor has flagged my use of capitalisation in "Section" and "Chapter" as possibly incorrect. I have googled about a bit and I see mixed opinions.  So my question is, when writing a computer science Ph.D. thesis, what is the correct way to capitalise "Section", "Chapter", "Appendix", "Figure", "Table", ... ?  For example, what is the correct capitalisation for the following:   "In Chapter 3, it was shown that..." "In the previous Section, a method was presented to..." "The graph in Figure 3 shows..." Do any clones refuse Order 66? When the clones are issued      telling them to turn on the Jedi,    do any of them refuse to carry out the order? Java multiline string How can I find a mentor to critique my work? Are all limits solvable without L'Hôpital Rule or Series Expansion alias to take a parameter and exit after execution Where can I find historical data on arrival and departure times of a particular flight? Where can I find historical data on flights, specifically Delta international flights?  I need to find out about cancellations, diversions and any other flight data pertaining on particular route at a given time.  This source has to be official and stand up to legal scrutiny. Conditional typesetting / build Let's say I have .tex file which is a set of problems and solutions, of which I want to make two pdf files, one which includes the solutions and one which doesn't. so I need to build the .tex file under two different modes, and specify that parts of the document be ignored under one of the modes.  This is something common in programming context. e.g. in C++ i can code  #ifdef DEBUG   // do this additional stuff ... #endif   How can I do something equivalent in latex? "Has been" vs "was" Would you please explain the difference between these two sentences?     Spain ceded (or gave) Puerto Rico to the United States. Since then, Puerto Rico has been a U.S. territory.      Spain ceded(or gave) Puerto Rico to the United States. Since then, Puerto Rico was a U.S. territory.   I am stuck between 'has been' and 'was' in the above sentences. Dimension of cone of projective variety How do you connect to multiple MySQL databases on a single webpage? I have information spread out across a few databases and want to put all the information onto one webpage using PHP.  I was wondering how I can connect to multiple databases on a single PHP webpage.  I know how to connect to a single database using:  $dbh = mysql_connect($hostname, $username, $password)          or die("Unable to connect to MySQL");   However, can I just use multiple "mysql_connect" commands to open the other databases, and how would PHP know what database I want the information pulled from if I do have multiple databases connected. I had two drives partitioned the same and running two RAID partitions on each.  One died and I replaced it under warranty for the same model.  While trying to partition it, the first partition can only start on sector 2048, instead of 63 that was before. Drive have different geometry as previous and remaining ones. (Fewer heads/more cylinders)  Old drive:  $ sudo fdisk -c -u -l /dev/sdb   Disk /dev/sdb: 2000.4 GB, 2000398934016 bytes 255 heads, 63 sectors/track, 243201 cylinders, total 3907029168 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x000aa189     Device Boot      Start         End      Blocks   Id  System /dev/sdb1   *          63   174080339    87040138+  83  Linux /dev/sdb2       174080340   182482334     4200997+  82  Linux swap / Solaris /dev/sdb3       182482335  3907024064  1862270865   fd  Linux raid autodetect   Remanufactured drive received from warranty:  $ sudo fdisk -c -u -l /dev/sda  Disk /dev/sda: 2000.4 GB, 2000398934016 bytes 81 heads, 63 sectors/track, 765633 cylinders, total 3907029168 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x000d0b5d     Device Boot      Start         End      Blocks   Id  System /dev/sda1            2048  ...   Why is that? Why do the $n \times n$ non-singular matrices form an "open" set?