How to Center a Image Shape in CSS
Center image element in parent div
How do I upgrade to a newer version of Ubuntu? Density of states for arbitrary dispersion relation If I have a 3D dispersion relation   $E=E(k_x, k_y, k_z)$ I have an equation for the density of states, which is   $D(E)=\frac{1}{\nabla_k E}\int\frac{dS}{(2\pi)^3}$  1) I am confused about the integral. What am I integrating over, exactly? It must have units of the $k$ vector, so it's a k-space integral, but what is the surface that is relevant?  3) Where does that equation come from, how is it derived? Process substitution and pipe Prove that the number $19\cdot8^n+17$ is not prime, $n\in\mathbb{Z}^+$ On a Google search, I've notice that often the "trick" involves factoring the expression (and thus showing that the expression isn't prime), but I can't see it. Is this how you would go about it in this case, or would that be a dead end? Any hints? Given a number, how do I discover in what table and column it could be found within? I don't care if it's fast, it just needs to work. So basically, I'd like to use iwconfig to connect to my wifi network when I'm not inside X. But I just don't see a way to do it in the man page. Any idea? Does each season of Game of Thrones roughly equal a book? Does each current Game of Thrones season roughly equal one A Song of Ice and Fire book? And do we know which future seasons will cover which books?  I am planning to read the first book after the TV show has finished depicting the events in the first book. I would like to know if after each TV season ends I can expect to be able to read a book covering the events depicted on screen? Leagues still count association bonus Is it supposed to be a HTML or an HTML I've seen many people who say:     This is a HTML page.   Yet I've also seen many people who say:     This is an HTML page.   Are both usages equally correct?  Or, which is the grammatically correct one?       Possible Duplicates: How do I install HP P1102W printer driver How to find the roots of $x^4 +1$ I'm trying to find the roots of $x^4+1$. I've already found in this site solutions for polynomials like this $x^n+a$, where $a$ is a negative term. I don't remember how to solve an equation when $a$ is a positive term as the equation above.  Thanks "Access denied" when trying to end a process on Windows 8 Let $f:A\rightarrow B$ and $C\subset B,D\subset B$. Prove that $f^{-1}(C\backslash D)=f^{-1}(C)\backslash f^{-1}(D)$ How are the degrees of freedom in the emmeans package calculated? - R When updating, I get the following error message:   W: The repository 'http://ppa.launchpad.net/mc3man/trusty-media/ubuntu xenial Release' does not have a Release file.   Here, I find another statement on this error:   This recommends removing certain PPAs; and, I'm not sure if I should do that since it might mean not getting the updates that I need.    Is this what I should do? I have run out of space on my WinXP virtual machine, which I only gave 10 GB space for when I created it.  Is there an easy way to increase it to, say, 20 GB?  I can't see any obvious option in VirtualBox settings.    The suggestion below gives this error  wim@wim-ubuntu:/media/data/winxp_vm$ VBoxManage modifyhd wim.vdi --resize 20000 VBoxManage: error: Cannot register the hard disk '/media/data/winxp_vm/wim.vdi' {46284957-2c09-4e70-8a49-bfbe0f7f681d} because a hard disk '/home/wim/VirtualBox VMs/winxp_vm/wim.vdi' with UUID {46284957-2c09-4e70-8a49-bfbe0f7f681d} already exists VBoxManage: error: Details: code NS_ERROR_INVALID_ARG (0x80070057), component VirtualBox, interface IVirtualBox, callee nsISupports Context: "OpenMedium(Bstr(pszFilenameOrUuid).raw(), enmDevType, AccessMode_ReadWrite, fForceNewUuidOnOpen, pMedium.asOutParam())" at line 210 of file VBoxManageDisk.cpp     Removing the .vdi from VirtualBox before calling VBoxManage command, then adding it back in, was successful.  But now I can't boot the virtual machine, I get this worrying screen:    By the way, it says FATAL: Could not read from the boot medium!  System halted.    The vdi must be reattached to the VM after VBoxManage command.  Further, the partition will need to be resized from WITHIN windows, because you will have this empty space:    I was able to resize the partition easily using a bit of freeware called . I am a newbie in Latex. My goal is to have the word "Chapter" in the title of any chapter, and the word "Appendix" in the title of appendix. I also want to add "Appendix" in TOC. However, using the following MWE from my university, I end up having "Appendix A" in TOC. How can I remove the letter "A" in TOC.  \documentclass[12]{thesis}  \RequirePackage{tocloft} \RequirePackage{titlesec} \usepackage[titletoc]{appendix}  \newcommand{\spacemultiplier}{1.5} \renewcommand{\baselinestretch}{\spacemultiplier}\normalsize  \renewcommand{\frontmatter}{ %TABLE OF CONTENTS \addcontentsline{toc}{chapter}{Contents} {\renewcommand{\baselinestretch}{1}\normalsize \tableofcontents } \newpage \titleformat{\chapter}[display]{\renewcommand{\baselinestretch}{1.5}\LARGE\sc\fillast}{Chapter   \thechapter}{0pt}{}[\renewcommand{\baselinestretch}{\spacemultiplier}\normalsize] \titlespacing{\chapter}{0pt}{1.4cm}{20pt} \setcounter{chapter}{0} }  % Appendix setup \newcommand{\universityappendix}{ \appendix \titleformat{\chapter}[display]{\renewcommand{\baselinestretch}{1.5}\normalsize \LARGE\sc\fillast}{Appendix}{0pt}{} \titlespacing{\chapter}{0pt}{-30pt}{20pt} \renewcommand{\baselinestretch}{1.5}\normalsize }   \begin{document}  \frontmatter  \chapter{blah blah} This is a chapter  \universityappendix \begin{appendices} \chapter{blah blah} this is appendix \end{appendices} \end{document}   Thanks Is there a single word for “one who explains his point of view very clearly”? Let $\phi : R \to S$ be a homomorphism. If $N$ is an ideal of $S$, then $\phi ^{-1} (N)$ is an ideal of $R$. $4$ letter words taken from the letters of CONCENTRATIONS How many words with or without meaning can be made from the letters of the word CONCENTRATIONS by taking $4$ letters at a time?  There are  $14$ letters total present in the word. $4$ letters can be picked in $14\choose 4$ ways. $4$ letters can be arranged in $4!$ ways. So ideally answer has to be ${14\choose 4} * 4!$. But I know this answer is wrong because some letters are repeating. How do I solve this then? I appreciate any help.