access built in HDD from formated windows to ubuntu SSD
Install Ubuntu 12.10 instead of Windows 8
GPG can't check signature Does every non-trivial subgroup of $S_9$ containing an odd permutation necessarily contain a transposition?    Here $S_9$ denotes the group of all permutations (i.e. bijections with itself) of the set $\{1,2, \ldots, 9 \}$ under the binary operation of composition of functions.   By a transposition is meant a permutation that leaves all elements except two fixed, mapping either of these two onto the other.   A permutation can only be expressed either as a product of an even number of transpositions or as a product of an odd number of transpositions (but not both) and as such is defined to be even or odd, respectively.   Reference: Fraleigh p. 95  Question 23d. in A First Course in Abstract Algebra Mis-aligned shapefiles in QGIS? Sauron knew that the One Ring could be destroyed only in Mount Doom, where it was forged. From Sauron's perspective, no one would think about destroying the One Ring. But if someone did, then Mount Doom would be the only place to do so.  Why did he keep Mount Doom active? Wasn't the risk too high? Meaning: To This Day I have this code:  DECLARE @MyTable AS TABLE (    [Month] INT,    Salary INT );  INSERT INTO @MyTable VALUES (1,2000), (1,3100);  SELECT [Month], Salary FROM @MyTable;   Output:    I want to concat the Salary (grouping by month) so that it will be NVARCHAR like this: '2000,3100'  How would I do this efficiently? Is there a function to round a float in C or do I need to write my own?       float conver = 45.592346543;   I would like to round the actual value to one decimal place, conver = 45.6. Script to raise a single window to the front I have a time series that shows a nonstationary seasonal autoregressive component as well as known heteroshedasticity. In order to model the series, I have fit a seasonal ARIMA model for the mean with the auto.arima model in the forecast package in R and a GARCH model on the residuals of the ARIMA model.   Is the procedure of sequentially estimating ARIMA and GARCH model correct or would it have been better to jointly model the mean and the variance of the series? If this were correct, is there a (possibly R) function to do it? How to sandbox applications? I want to run small untrusted programs, but restrict them from accessing any files outside of their folder, network access, and everything else that they don't really need. What is the simplest way to achieve this? Can I have multiple background images using CSS? Is it possible to have two background images?  For instance, I'd like to have one image repeat across the top (repeat-x), and another repeat across the entire page (repeat), where the one across the entire page is behind the one which repeats across the top.  I've found that I can achieve the desired effect for two background images by setting the background of html and body:  html {     background: url(images/bg.png); }  body {     background: url(images/bgtop.png) repeat-x; }   Is this "good" CSS?  Is there a better method?  And what if I wanted three or more background images? Prove that $(ma, mb) = |m|(a, b)\ $ [GCD & LCM Distributive Law] I'm trying to prove that $(ma, mb) = $|$m$|$(a, b)$ , where $(ma, mb)$ is the greatest common divisor between $ma$ and $mb$. My thoughts: If $(ma, mb) = d$ , then $d$|$ma$ and $d$|$mb$ → $d$|$max + mby$ → $d$|$m(ax+by)$. This implies that $d$|$m$ or $d$|$(ax+by)$. This is the same as  $d$|$m$ or $d$|$a$ and $d$|$b$, so $d$|$m$ or $d$|$(a,b)$. This is the same as $d$|$m|$ or $d|(a,b)$, so $d$|$|m|(a,b)$. I don't know what to do. $\sum_i x_i^n = 0$ for all $n$ implies $x_i = 0$ Here is a statement that seems prima facie obvious, but when I try to prove it, I am lost.  Let $x_1 , x_2, \dots, x_k$ be complex numbers satisfying:  $$x_1 + x_2+ \dots + x_k = 0$$  $$x_1^2 + x_2^2+ \dots + x_k^2 = 0$$  $$x_1^3 + x_2^3+ \dots + x_k^3 = 0$$  $$\dots$$  Then $x_1 = x_2 = \dots = x_k = 0$.    The statement seems obvious because we have more than $k$ constraints (constraints that are in some sense, "independent") on $k$ variables, so they should determine the variables uniquely.  But my attempts so far of formalizing this intuition have failed.  So, how do you prove this statement?  Is there a generalization of my intuition? FME - Calculate distance of point along a line I have created an FME workspace which inputs a pipeline as well as other linear features which cross it (waterways, roads, railways, fences, other pipelines, etc).  The output is a point file which contains the crossing type.  What I would like to do is calculate the distance along the pipe from the start of the pipeline for each intersection.  So, as you travel along the pipeline, the distance attribute will increase.   I'm thinking that I'll need to use some of the linear referencing tools like MeasureGenerator, MeasureExtractor, or something like that, but I'm not sure how to do so.  Does anyone have an idea of how to do this? external variable in awk If user input is inserted without modification into an SQL query, then the application becomes vulnerable to , like in the following example:  $unsafe_variable = $_POST['user_input'];   mysql_query("INSERT INTO `table` (`column`) VALUES ('$unsafe_variable')");   That's because the user can input something like value'); DROP TABLE table;--, and the query becomes:  INSERT INTO `table` (`column`) VALUES('value'); DROP TABLE table;--')   What can be done to prevent this from happening? Number of elements of a finite field What's the difference between the simple past tense and the present perfect? The simple past tense indicates that an activity or situation began   and ended at a particular time in the past.      The present perfect expresses the idea that something happened (or   never happened) before now, at an unspecified time in the past.The   exact time it happened is not important. It also expresses the   repetition of an activity before now. The exact time of each   repetition is not important.   Even though I understand the explanation above, I can't figure out: If the present perfect states the idea that something happened in the past, why not use the simple past?  For example, would you please explain the following sentence to tell the difference between these two tenses?         The plane crashed there.    The plane has crashed there.      What is the biggest difference between them? Prove or show a counter example for: $\forall a, b, c \in \mathbb Z$, if $ab\mid c$ then $a\mid c$ and $b\mid c$ I'm working on my Discrete Mathematics homework and they are asking me this:  Prove or show a counterexample for: $\forall a, b, c \in \mathbb Z$, if $ab\mid c$ then $a\mid c$ and $b\mid c$  I'm not completely sure how to prove it. I was thinking to find a counterexample like zero but I'm not sure if that it's going to work. Or maybe try to approach it backwards?   I'm a little bit lost Though tangentially related to another post on MathOverflow (), the questions below are mainly out of curiosity. They may be very-well known ones with very well-known answers, but...    Suppose $\Sigma$ is a sigma-algebra over a set, $X$. For any given topology, $\tau$, on $X$ denote by $\mathfrak{B}_X(\tau)$ the Borel algebra over $X$ generated by $\tau$.     Question 1. Does there exist a topology, $\tau$, on $X$ such that $\Sigma = \mathfrak{B}_X(\tau)$?   If the answer to the previous question is affirmative, it makes sense to ask for the following too:     Question 2. Denote by ${\frak{T}}_X(\Sigma)$ the family of all topologies $\tau$ on $X$ such that $\Sigma = \mathfrak{B}_X(\tau)$ and let $\tau_X(\Sigma) := \bigcap_{\tau \in {\frak{T}}_X(\Sigma)} \tau$. Is $\Sigma = \mathfrak{B}_X({\frak{T}}_X(\Sigma))$?   Updates. Q2 was answered in the negative by Mike ().