Similar to the question here, , I have a similar but different question.   I am an SG passport holder, which allows me to be in the UK for 6 months.   Question 1: If I leave UK and visit somewhere (i.e. France), does the 6 months reset when I return?  E.g. I leave UK on the 100th day. I travel to France for 7 days. When I return to UK, am I left with 80 days or it resets to 180 days?  Question 2:  Schengen area has a limit of 90 days per 180 days. Is there something similar in UK?   Thanks!
I am a US citizen and have recently visted the UK  with simply a passport which allowed me to vist for 6months I have heard rumors that I am obligated to stay in the US for a Equal amount of time that I have visited the UK before I am able to return, but I am struggling tour no any proof of this obligation .. Am I missing somthing or is it simply not true
What language is the Ubuntu Software Center written in? Just been wondering, since elementary AppCenter is written with Vala and Gtk+3.  Also, what GUI wrapper does it use? Display Blank when Referencing Blank Cell in Excel 2010 I have an Excel 2010 workbook that contains a number of individual worksheets. The cells on one of the sheets are linked to individual cells on two other worksheets in the same workbook.  I'm using a direct cell reference that essentially says that whatever value is entered into a particular cell on one sheet also populates cells on two other sheets.  I used the (=) function with the cell reference to accomplish this.  The issue I'm running into is that, even when the primary cell is left blank, the cells that populate from that primary cell will display 0, rather than remaining blank themselves.  I want the subordinate cells to remain blank if the primary cell they're linked to is blank. Have the guys from the show Impractical Jokers gotten into any major trouble because of the nature of their show?   Eg: have they been physically assaulted or has anyone thrown a law suit on them? Probability Problem with $n$ keys A woman has $n$ keys, one of which will open a door. a)If she tries the keys at random, discarding those that do not work, what is the probability that she will open the door on her $k^{\mathrm{th}}$ try?  Attempt: On her first try, she will have the correct key with probability $\frac1n$. If this does not work, she will throw it away and on her second attempt, she will have the correct key with probability $\frac1{(n-1)}$. So on her $k^{\mathrm{th}}$ try, the probability is $\frac1{(n-(k-1))}$ This does not agree with my solutions.   b)The same as above but this time she does not discard the keys if they do not work.  Attempt: We want the probability on her $k^{\mathrm{th}}$ try. So we want to consider the probability that she must fail on her $k-1$ attempts. Since she keeps all her keys, the correct one is chosen with probability $\frac1n$ for each trial. So the desired probability is $(1-\frac{1}{n})^{k-1} (\frac1n)^k$. Again, does not agree with solutions.  I can't really see any mistake in my logic. Can anyone offer any advice? Many thanks I'm trying to factorise $$ x^3z - x^3y - y^3z + yz^3 + xy^3 - xz^3 $$ into four linear factors.  By plugging it into WolframAlpha I've learned that it's $$-(x-y)(x-z)(y-z)(x+y+z)$$  My question is: what are the steps involved in factorising the expression? Is there a method I don't know about that I'd have access to with my limited maths?  Really appreciate any help! How to convert a Collection to List? Probability that $m$ balls will fall into first box Suppose we have $n$ balls that are randomly distributed into $N$ boxes. Find the probability that $m$ balls will fall into the first box. Assume that all $N^m$ arrangements are equally likely.  Attempt: First, we notice that for the first box, we have $n$ choices, and for the second box we also have $n$ choices, and so on. Thus, we have $n^N$ ways to place the balls into the boxes. Pick $m$ balls out of the total $n$ balls, that gives ${n \choose m}$. In how many ways can these $m$ balls go into the first box? Well, in just ${1 \choose 1 }= 1 $ ways. Thus, $$ P = \frac{ {n \choose m } }{n^N } $$ Is this correct? What is the difference between Newtonian and Lagrangian mechanics in a nutshell? What is Lagrangian mechanics, and what's the difference compared to Newtonian mechanics? I'm a mathematician/computer scientist, not a physicist, so I'm kind of looking for something like the explanation of the Lagrangian formulation of mechanics you'd give to someone who just finished a semester of college physics.  Things I'm hoping to have explained to me:   What's the overall difference in layman's terms? From what I've read so far, it sounds like Newtonian mechanics takes a more local "cause-and-effect"/"apply a force, get a reaction" view, while Lagrangian mechanics takes a more global "minimize this quantity" view. Or, to put it more axiomatically, Newtonian mechanics starts with Newton's three laws of motion, while Lagrangian mechanics starts with the Principle of Least Action. How do the approaches differ mathematically/when you're trying to solve a problem? Kind of similar to above, I'm guessing that Newtonian solutions start with drawing a bunch of force vectors, while Lagrangian solutions start with defining some function (calculating the Lagrangian...?) you want to minimize, but I really have no idea. What are the pros/cons of each approach? What questions are more naturally solved in each? For example, I believe Fermat's Principle of Least Time is something that's very naturally explained in Lagrangian mechanics ("minimize the time it takes to get between these two points"), but more difficult to explain in Newtonian mechanics since it requires knowing your endpoint. How can I say this? Good math books for physicists In his first lesson (transcripted in "Tips on Physics"), Feynman talks about math for physicists in a very cool and practical way. And at the end of the section he talks something like "so the first thing to do is to learn to learn derivative, integral and algebra" (I don't know how much precise I'm being because I've read it in Portuguese). I would to know if there is some book that deals with math as Feynman did it in this lesson (respecting formalities, but teaching how to use the practical rules)? Also, someone have any recommendations for algebra book (college level)? Suppose that $f:\Bbb R\to \Bbb R$ is continuous and that $f(x)\to 0$ as $x\to \pm\infty$. Prove that $f$ is uniformly continuous.   Since $f(x)\to 0$ as $x\to \pm\infty$ we have $|f(x)|&lt;\epsilon $ whenever $x&lt;-K$ and $x&gt;K$ where $K&gt;0$.  Also $f$ is uniformly continuous on $[-K,K]$ as the domain is compact.  Hence $f$ is uniformly continuous in $(-\infty,-K)\cup [-K,K]\cup (K,\infty)$.  But how to conclude that $f$ is uniformly continuous on $\Bbb R$ from above as I may chose $x\in (-\infty,-K);y\in [-K,K]$ ,how to conclude that $|f(x)-f(y)|&lt;\epsilon $ from above for a given $\epsilon$?  Please suggest the edits required. Available space not changing when resizing a partition Why does the CRT formula yield a solution of a congruence system? I have added the png transparent image with the setting and its not showing transparent black background is seen. I have the base color aluminum and i want to add that logo of png on to it. The image is black letter with transparent background why its showing in white letters and black background. May i know where im going wrong any suggestion or help. How to calculate the limit of $\frac{a_n}{n^2}$ for the sequence $a_{n+1}=a_n+\frac{2 a_{n-1}}{n+1}$? Assume $\{a_n\}$is a sequence which  satisfies the following recursion formula: $$a_{n+1}=a_n+\frac{2a_{n-1}}{n+1}~(n\geqslant 1).$$ and $a_0=\pi,a_1=\pi^2 $. How to compute $\displaystyle\lim_{n\to \infty}\frac{a_n}{n^2}$? butt, bottom, buttock and ass? A woman's butt was allegedly touched by a man several times during a commute on the MRT.   How to use butt, bottom, buttock and ass? I am confusing with these words. The real meaning of time dilation The extension of smooth function Using notify-send with cron I am using Arch Linux with KDE/Awesome WM. I am trying to get  notify-send to work with cron.   I have tried setting DISPLAY/XAUTHORITY variables, and running notify-send with "sudo -u", all without result.  I am able to call notify-send interactively from the session and get notifications.  FWIW, the cron job is running fine which I verified by echoing stuff to a temporary file. It is just the "notify-send" that fails to work.  Code:  [matrix@morpheus ~]$ crontab -l * * * * *  /home/matrix/scripts/notify.sh  [matrix@morpheus ~]$ cat /home/matrix/scripts/notify.sh #!/bin/bash export DISPLAY=127.0.0.1:0.0 export XAUTHORITY=/home/matrix/.Xauthority echo "testing cron" &gt;/tmp/crontest sudo -u matrix /usr/bin/notify-send "hello" echo "now tested notify-send" &gt;&gt;/tmp/crontest  [matrix@morpheus ~]$ cat /tmp/crontest testing cron now tested notify-send  [matrix@morpheus ~]$    As you can see the echo before &amp; after notify-send worked. Also I have tried setting DISPLAY=:0.0   UPDATE: I searched a bit more and  needs to be set. And after hardcoding this using the value I got from my interactive session, the tiny little "hello" message started popping up on the screen every minute!   But the catch is this variable is not permanent per that post, so I'll have try the the named pipe solution suggested there.   [matrix@morpheus ~]$ cat scripts/notify.sh #!/bin/bash export DISPLAY=127.0.0.1:0.0 export XAUTHORITY=/home/matrix/.Xauthority export DBUS_SESSION_BUS_ADDRESS=unix:abstract=/tmp/dbus-BouFPQKgqg,guid=64b483d7678f2196e780849752e67d3c echo "testing cron" &gt;/tmp/crontest /usr/bin/notify-send "hello" echo "now tested notify-send" &gt;&gt;/tmp/crontest   Since cron doesn't seem to support notify-send (at least not directly) is there some other notification system that is more cron friendly that I can use? I have attached an image as an example below. I want to twist a rectangle. Do I have to convert that rectangle into a curve or into mesh and then twist it with ctrl+T?   Please explain with an example.