I have lived in Germany since 2011 and I have had refugee status since 2017. My mother died in 2013. I want to visit her grave. How can I do that? I need only 10 days to go back to my country Pakistan.
I was recently granted German refugee status with a travel document and, in my interview, I told them I would never go back to my home country, Iraq. Now, someone I loved died in my country.  Is it possible for me to leave and return to the Schengen area, using my Iraqi passport? Would German Immigration notice and would it revoke my refugee status?  Would I be able to use both my Iraqi passport and my German travel documents? Would the German authorities know if I did this?
Energy conservation in General Relativity Prove $\lim_{x \rightarrow 0} \frac {\sin(x)}{x} = 1$ with the epsilon-delta definition of limit. It is well known that   $$\lim_{x \rightarrow 0} \frac {\sin(x)}{x} = 1$$  I know several proofs of this: the geometric proof shows that $\cos(\theta)\leq\frac {\sin(\theta)}{\theta}\leq1$ and using the Squeeze Theorem I conclude that $\lim_{x \rightarrow 0} \frac {\sin(x)}{x} = 1$, other proof uses the Maclaurin series of $\sin(x)$. My question is: is there a demonstration of this limit using the epsilon-delta definition of limit? How to add a subclass as a subview so that background of subview is set in front of superview Would it be possible for some to bend two elements? After reading this question  While it seems that it would break one of the rules of the show, that only the avatar can master all four elements. There would also be good reasons as to why someone couldn't learn all four, there is always the opposing element that is hardest for the Avatar to learn. I don't see any reason why someone couldn't learn to bend two elements (not master, but just bend since Thadeus's Answer  to the previous question is apparently the Definitive Answer on the subject.)    Many benders do learn to bend beyond their element such as Toph becoming a metal bender and Katarra bending blood. Now metal is considered part of the Earth but so is sand and it seems that sand is moved more like water. Iroh was able to adapt a water bender technique to fire bending which means it is possible to learn and use different bending styles. Also Iroh spent time connecting to the spirit world and that seems to be the main reason the Avatar is able to bend all 4 elements. So if someone was connected to the spirit world or even their past life that would fulfill that requirement.   Would it be possible to bend two elements?  There do seem to be times where it has been done in the series such as bending mud which is both Earth and Water. And there would definitely be limits such as a Earth bender couldn't bend Air and a Water bender couldn't bend Fire. But why couldn't a Fire Bender learn to bend Air. They both use breath control as a main focus of their bending. It also states on the Energybending wiki entry that all bending used to be done as an inner bending but that it became element bending.   So with new bending techniques being formed all the time, already stated used of combined elements being used, an assumed spiritual connection to a past life or a spiritual journey been taken, energybending rediscovered is it possible that two elements could be bent by one bender who is not the Avatar? WiFi repeatedly asks for password (Ubuntu 12.10 fresh) I'm sure the passphrase is correct 100% but Wifi keeps asking for authentication and never connects. What can I do? I've tried removing the networks, resetting the router, changing the password, rebooting Ubuntu, disabling IPv6.  Also, it worked until earlier today and then stopped. All my other devices log in fine. What is tail recursion? Whilst starting to learn lisp, I've come across the term tail-recursive. What does it mean exactly? Eeeek! Code blocks are misbehaving! So code blocks in questions and answers on the android app (inline included) seem to be scared of me putting my finger in them. When I poke them, they only move over two columns!  (For clarity, these are the code blocks that overlap the TextArea view because they've been eating too much)  The intended behaviour here is that when I press my finger into a code block, the touch event should register a drag; at current, I try to scroll inside a code block and I end up switching to question or answer view instead, over and over.  EDIT:  Something tells me this is status-bydesign because the text is deliberately cut off (probably inviting you to click on the code block and expand it; UX Decision?): Add new alias to Gmail without SMTP (forwarding-only address) The product of $n$ consecutive integers is divisible by $n$ factorial How can we prove that the product of $n$ consecutive integers is divisible by $n$ factorial?     Note: In this  and the comments here the OP has clarified that he seeks a proof that "does not use the properties of binomial coefficients". Please post answers in said newer thread so that this incorrectly-posed question may be closed as a duplicate. I've upgraded from 12.04 to 14.04 via command-line when my system froze, had to do REISUB and dpkg --configure -a to recover from crash after rebooting.  Now everything seems to work except automatically mounting external thumb drives and external hard disk drives. After plugging in said drives, they fail to show up on the left pane and remains unmounted. I can see the device if I run lsusb and fdisk though, so it's possibly to manually mount it but I'd rather resolve why it's not automatically mounting. When applying for post-doctoral and faculty positions you are typically asked for three (sometimes more) reference letters to support your application.    Given that it is competitive out there, it also makes sense to apply for all positions that are good matches to your qualifications and career development goals (in the case of post-docs).  Sometimes this may mean asking for several reference letters (or pre-application "can you support me if required?" requests) in a short space of time.  Also, there may only be a small pool of people (i.e. 3 or 4) who know your work sufficiently well to give an excellent reference.  I have also been told that referees want to help you out, and that there is no reason to fear asking them.  And, that in many cases once a letter is written it can typically be quickly repurposed.  But there must be a breaking point.  How do I manage this without being disrespectful?  How many requests in a given unit of time is too many, or harms my credibility?   I am asking this question in this forum, as I am interested in the norms in the academic world, which are often somewhat different than the rest of the working world. Privacy leak in permalink? Update (Jan 8, 2019) This is now 8 years old, but still getting occasional upvotes/attention, so I thought it's worth giving a summary of the current state.  Despite originally being , over the last decade some changes have made the privacy implications much clearer.  You now click &quot;share&quot; instead of &quot;link&quot;, and the pop-up is very explicit that the link includes your user ID. There is a  asking that this user ID be anonymized or hashed, to allow users to earn publicity badges (the intention behind having the user ID present in the URL, as per ) while eliminating the privacy issue. Original Post It seems to me there is something of a privacy leak when permalinking to a question.  For what I would assume is the purposes of tracking which user is responsible for bringing traffic back to an SE site (for badges, etc.), the user ID of the user obtaining the permanent link . I wouldn't argue that this shouldn't be the case, but I find no warning or mention of this when I do these actions.  I'm sure I'm not the only one that doesn't desire anonymity on SO but would like at least pseudonymity on some places I might share a SO link, such as on a random blog.  As a user, I would not expect sharing a permanent link to leak my identity.   Unless you are familiar with Stack Exchange links or your own userID, it's certainly not obvious by looking at the link that it includes your personal info.  It'd be nice to have fair warning that using that feature will do so, and perhaps provide/describe the workaround: to simply remove the user-id segment from the URL.  Other features would be a preference that formats future permanent links to exclude the user id. Example (from this question)  Permalink:  Link to my user page: What's the term in music, where the singer uses words without meaning? I've been searching for the word, which is used for describing parts of lyrics, where the singer sings for example the whole refrain only using words of syllables without any meaning. Maybe you could help? (here's one song with that type of refrain: ) After searching here:    I am still curious about this.  Is it possible to derive the standard error of a regression coefficient from summary data alone?   E.g., assume we are given the following variance-covariance matrix.  $\begin{bmatrix}Var(X) &amp; Cov(X,Y)\\Cov(X,Y) &amp; Var(Y)\end{bmatrix}$  We can derive the regression coefficient $\beta_{XY} = Cov(X,Y) / Var(X)$.  Given a specific n, is it possible to derive the standard error of $\beta$ as well? If so, which formula is being used? It appears that all formulas for regression standard errors that I could find assume that you know the variance of residuals of the regression, which we don't know from summary data alone.  ---UPDATE--- Based on feedback by Greg and whuber, I am now at a point, where I know that  $\sigma^2(b) = \sigma^2(X'X)^{-1}=\sigma^2(Var(X)(n-1))^{-1}$,  but typically matrix formulas for the standard error of $b$ then note that $\sigma^2$, the unknown variance of the errors, is estimated with MSE.   Based on comments by whuber, sum of squares residuals is:  $Y'Y - bX'X$, which according to Greg can be spelled out as  $Var(Y)(n-1) - b(Var(x)(n-1))$  And to go from here to MSE, I think (?) all that is left is divide by n-2,  so $(Var(Y)(n-1) - b(Var(x)(n-1))) / (n-2)$  And plugging this all in yields:  $\sigma^2(b) =((Var(Y)(n-1) - b(Var(X)(n-1))) / (n-2))\times(Var(X)(n-1))^{-1}$  I will try to see if this works out in R, and will report back. If anyone sees something blatantly wrong, I appreciate the heads up. Why does sstatic.net serve cookies? According to :  This is a fast, cookieless domain intended for static content delivered to the   However, all responses from the server set a cookie anyway: $ http https://sstatic.net/ HTTP/1.1 200 OK CF-RAY: 162b88245bc406be-LHR Cache-Control: max-age=604800 Connection: keep-alive Content-Encoding: gzip Content-Type: text/html Date: Sun, 31 Aug 2014 19:11:04 GMT ETag: W/&quot;d5474fdfb5c3cf1:0&quot; Last-Modified: Fri, 29 Aug 2014 18:20:12 GMT Server: cloudflare-nginx Set-Cookie: __cfduid=db60cc6f3e7f6482e37f1f2b85c9dc5881409512264375; expires=Mon, 23-Dec-2019 23:50:00 GMT; path=/; domain=.sstatic.net; HttpOnly Transfer-Encoding: chunked Vary: Accept-Encoding [...]  Is this intentional, or just funny? Edited to add: I understand that the cookie is used to track visiting browsers so that cloudflare can distinguish them from misbehaving hosts using the same or a nearby IP address. However, if the policy is intentionally to serve cookies, then the self-documentation of sstatic.net as a &quot;cookieless domain&quot; is incorrect. Prove that if $d$ divides $n$ then $φ(d)$ divide $φ(n)$ for $φ$ denotes Euler’s $φ$-function.  I know that $d|n$ mean there exists some integer $k$ such that $n=kd$, but how can I use this to prove $φ(d)$ divide $φ(n)$ Current sensing nA to mA I need to sense the current of a target  through various periods of its on/sleep/off state and then need to send this data back to another interface MCU to read out the value. They will be both on the same board, powered by 5&nbsp;V USB.  However these are the requirements I have:   5&nbsp;V USB PSU Must be able to sense currents in the range of nA to mA with high    accuracy/precision. (I figure 1&nbsp;nA to 500&nbsp;mA) Only measure the current of the target MCU and not the interface. Must output maximum 3.3&nbsp;V interface MCU   I have looked at available options and current sense amplifiers by Texas Instruments can't sense nA due to higher bias currents. So therefore I feel I would need a precision amplifier.  However I am stuck on how to proceed with this because, I need to somehow have a automatic dynamic current range and I am fairly new to current sensing and am not really sure on all the specifics. What's optimal hardness for a kitchen knife blade? Many knife manufacturers provide the hardness value for the knife blade in the specifications - like 53HRC or 57 HRC.  What's the optimal hardness for kitchen knives? Do I always prefer the ones with higher hardness all else being equal? How to create subfloat figures (two in first row and one below)? I want to place three figures like this on the page:  (a) (b)   (c)   How do I achieve this using subfloat or any other method in LaTeX? The three figures need to have a common caption and label.  I have tried this:  \begin{figure}[h] \centering \begin{tabular}{c c} \subfloat[] { \includegraphics[scale=0.4]{1.pdf} } &amp; \subfloat[] { \includegraphics[scale=0.4]{2.pdf} } \\ \multicolumn{2}{c} \subfloat[] { \includegraphics[scale=0.6]{3.pdf} } \end{tabular} \caption{Some caption} \label{some-label} \end{figure}   But, this is displaying [] for the third figure instead of (c). Also it displays [] to one side of the page instead of center. Is there a way to find the number of files of a specific type without having to loop through all results inn a Directory.GetFiles() or similar method? I am looking for something like this:  int ComponentCount = MagicFindFileCount(@"c:\windows\system32", "*.dll");   I know that I can make a recursive function to call Directory.GetFiles , but it would be much cleaner if I could do this without all the iterating.  EDIT: If it is not possible to do this without recursing and iterating yourself, what would be the best way to do it?