As most probably know, in terraria, it is possible to replicate certain spawn conditions artificially in controlled conditions. One example is the meteorite in which having x amount of meteorite ore, meteor heads will spawn. Similarly in minecraft, Iron Golems can be farmed for iron if one were to artifically create a village large enough for them to spawn.  That said, in minecraft, it is stated in the wiki that wither skeletons spawn in nether fortresses. Is it possible to replicate the condition for wither skeletons to spawn just like one would do in terraria or perhaps like the Village Iron Golem farm?
What conditions are necessary for a Wither Skeleton to spawn naturally, and can I manipulate those conditions to increase the chance of them spawning?  I want to make a Wither Skeleton spawning pad in the Nether but I'm having trouble finding Wither Skeletons. I've only heard that they spawn in Nether Fortresses.
Can I install a ROM made for a different device? Suppose a vibrating fork exerts force to the air particles to compress which leads to the increase of internal energy (heat).This heat or energy given by the fork is given to the next layer of air and in this way, this energy makes sound. But if it was so, it will be isothermal. And Laplace told it was adiabatic. How can it be? I am confused. The heat energy infact is the energy given by the fork. If it is adiabatic, how can the air pass this energy ? When is Gauss' law not applicable? Protecting game assets through archiving I'm writing a game in C++ (with OpenGL) and am getting quite far into development. Currently I'm loading the data directly from different directories.  (E.G. I load textures from a /Data/Textures/...png)  This is fine, but not preferable. Ideally I would like to protect these assets without too much of a performance hit. I looked at other games that I own, both Indie and AAA and found that the majority of them archive the data. However, I am unable to access these archives with programs like Winrar Archiver which implies that they have some level of protection.  I'm not particularly knowledgeable in the field of encryption and data storage, so I may be overlooking something obvious but I would like to know how exactly I could achieve something similar.  (I am aware that competent individuals are able to use the GPU to gain access to the data but that's not preventable) How can I port forward with iptables? How can I display "recent folders" in the sidebar of "Save as" dialogue? I was using 14.04 and upgraded to 16.04 yesterday.   In 14.04 I had recent folders on top of the sidebar of the Save as dialogue when I saved something from the net (Firefox if that helps). But that feature disappeared in 16.04 and I really want to have it back.   Here is a picture of what I'm trying to explain:  (the save as dialogue in 16.04 without the recent folders on top) Why can some holodeck matter leave the holodeck, while other holodeck matter (notably people) cannot? This is in Windows, but answers for other operating systems can be handy to others.  Most guides say something to the effect of "hold down the Alt key and type in the code on the keypad".  This works fine for decimal codes (like 65 for 'A'), but not for  codes (like  for 'A').  Some applicatons provide other facilities that will allow hexadecimal Unicode character codes to be typed and then transformed.  Word allows you to type the code (such as 200f) and then convert it to Unicode by typing Alt-X.  I'm looking for a general method of doing this that will work with the standard input. Proof a $2^n$ by $2^n$ board can be filled using L shaped trominoes and 1 monomino Suppose we have an $2^n\times 2^n$ board. Prove you can use any rotation of L shaped trominoes and a monomino to fill the board completely.  You can mix different rotations in the same tililng. I have some files with different extensions such as *.pdf, *.mp3, *.jpg and a few others. All of them are stored in a parent directory.  How can I get a list of all extensions, create some folders based on these  extensions and then move all files into their relevant folders? How can I delete an account on a specific site? My account has 20 (!) sites associated to it.  I only use it for 3-5 sites.  To reduce clutter, I would like to delete my profiles that I do not use much.  I have went through , but when I enter the profile URL as:  http://russian.stackexchange.com/users/5772/alex   it gives the error message:     oops! this isn't a link to a valid profile   What procedure do I go through to delete my profile only on certain sites? 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. Volume of an n-simplex It's rather tedious to show using Fubini's Theorem and induction on $n$ that the volume of the region $x_1+x_2+...+x_n \leq 1$ with $x_1,...,x_n$ nonnegative is $\frac{1}{n!}$.  Is there an easier way to see this? "Insufficient storage" when trying to install new app Every time I go to install a new app, I get the message "Insufficient storage", and an unable to install anything!  I am using Samsung GT19060 my internal memory is 8GB. I have not downloaded anything but anytime I try to download something it will tell me low memory space. Extracting Windows 8 Start Screen Patterns Is there any way to extract the Windows 8 Start Screen patterns, in order to use them as standalone wallpapers on other systems?  For example see this screenshot:    I am interested in the dark blue background. I heard that this background is somehow adapted to your chosen color theme. So many different variations should exist.  Engadget has an article  briefly talking about these background patterns and the different color schemes. They call them "personalization tattoos".    Update:    I found the following page/guide:   This looks a very good way to achieve my goal. Unfortunately the guide seems to be dated.  I tried to find shsxs.dll on the RTM of Windows 8 without much luck. It looks like Microsoft changed the way they handle the background image. The file is nowhere to be found...  I also looked into uxtheme.dll, but it doesn't contain any interesting images.  Any new ideas? Any other *.dll with might be of interest here? I have gcc 7.3.0 on Ubuntu 18.04. But I am working on a project where I need gcc less than version 6. When I tried to install gcc 5.4 using sudo apt install gcc-5.4, I got this error:  Reading package lists... Done Building dependency tree        Reading state information... Done E: Unable to locate package gcc-5.4 E: Couldn't find any package by glob 'gcc-5.4' E: Couldn't find any package by regex 'gcc-5.4'     What is the appropriate way to install gcc 5.4? I've seen papers (e.g., in Science) where the first two authors are listed in non-alphabetical order, and yet there are asterisks behind their names to say that they contributed equally.   It seems strange to me, because if the two authors are in alphabetical order, then it could be that the first author contributed more or the two contributed equally, and this can be made clear with asterisks in the paper if it's the latter case. When they're in non-alphabetical order, however, if someone only sees the author list without seeing the paper, he/she will likely assume that the first author contributed most.  So my question is: Are there particular reasons why people do that? (This  is related, but I don't think the answers there get to my question.) Use dynamic variable names in JavaScript Quaternion for beginner I have 2 points in 3d space ,point A= &lt;5,3,6> and B=&lt;8,2,3>  I want to rotate "point B" by 30 degree from point A.  how do I solve this question using quaternion.  Plz, explain the steps.... Prove that $ n < 2^{n}$ for all natural numbers $n$. Prove that  $ n &lt; 2^{n}  $ for all natural numbers $n$.  I tried this with induction: Inequality clearly holds when $n=1$. Supposing that when $n=k$, $k&lt;2^{k}$. Considering $k+1 &lt;2^{k}+1$, but where do I go from here?  Any other methods maybe?