What if I fill liquid nitrogen in tube of two wheeler?? Is it OK?
I am completely new to riding bikes and know that are usually filled with air but nowadays some people fill them with Nitrogen instead.  I don't know why they prefer to fill their tires with nitrogen as it is more costly than filling them with air.  What are the benefits of filling tires with Nitrogen?
What books, journals, and/or electronic resources have you found most valuable for expanding your knowledge in the GIS field, and why? How to change from csh to bash as default shell I have csh as my default shell, as shown by echo $SHELL. I want to switch to bash as my default shell. I tried the following approaches to no avail:   With chsh I get:  chsh: can only change local entries; use ypchsh instead.  With ypchsh I get:  ypchsh: yppasswdd not running on NIS master host ("dcsun2").    I only have .chsrc in my home directory and I cannot find any .profile files in /etc. How can I change my default shell to bash? Pretty printing XML with javascript How do I change my login provider(s)? How do I remove my "page not found" pages from Google's index? I have a wordpress site that has had a large number of blog posts removed. How can i ask google to remove all these 404 page not founds, but leave the active blog posts. I see the removal tool in google webmasters but it doesnt say if it will just remove the 404s. I understand 404s naturally are removed from the index, but i want to expedite this. addtocontents not working with certain other packages This is a follow up question on   How do I change the toc dept mid document while using packages (in this case only mathtools).  An example:  \documentclass[a4paper,10pt,oneside]{book}  \usepackage{mathtools}  \begin{document}   \frontmatter             \chapter{hello}  \section{hello}  \subsection{hello}  \subsubsection{hello}   \setcounter{tocdepth}{3}  \tableofcontents   \mainmatter   \chapter{hello}  \section{hello}  \subsection{hello}  \subsubsection{hello}   \chapter{hello}  \section{hello}  \subsection{hello}  \subsubsection{hello}   \appendix   \addtocontents{toc}{\setcounter{tocdepth}{0}}   \chapter{hello}  \section{hello}  \subsection{hello}  \subsubsection{hello}   \chapter{hello}  \section{hello}  \subsection{hello}  \subsubsection{hello}  \end{document}   This example generates an error and very strangely puts an exclamation mark in the ToC as you can see here   however when I comment out the \usepackage{mathtools} it suddenly works again or replacing it with a different package such as \usepackage[T1]{fontenc} also generates no errors.  But this is not limited to just this specific package, certain other packages also introduce the same behavior (I just took this package to keep the example small). Is it okay to use my US visa after a name change? I had my US visa about 7 month age, and I had to renew my passport for certain circumstances, so there was a mismatch in the name between both the visa and the new passport, you see they had to put my grand grandfather's name which was not on the old passport nor the visa, the name on old passport and visa is: Abdelrahman Samy Ali Mohammed and the new passport is: Abdelrahman Samy Ali Ibrahim Mohammed. My grand grandfather's name is Ibrahim, so the question is that gonna cause me any troubles concerning my entry to the US? is there any document should I consider taking it while i'm traveling?  Thanks,, How can I check if a directory exists in a Bash shell script? What command can be used to check if a directory exists or not, within a Bash shell script? Cardinality of a totally ordered union Let $(X_{\alpha})_{\alpha \in A}, (Y_{\alpha})_{\alpha \in A}$ be families of sets such that for $\{X_{\alpha} \mid \alpha \in A \}$ and $\{Y_{\alpha} \mid \alpha \in A \}$ are totally ordered by inclusion. We have $(X_{\alpha},Y_{\alpha}) \neq (X_{\beta},Y_{\beta})$ for $\alpha \neq \beta$. Suppose that $|X_{\alpha}| \leq |Y_{\alpha}|$ for any $\alpha \in A$. It is true that $|\bigcup_{\alpha} X_{\alpha}| \leq |\bigcup_{\alpha} Y_{\alpha}|$? What is the actual mechanism behind the reflection of various colored light by material of different color? When light (composed of photons with different frequency and wavelength) falls on a material, some of it gets absorbed and some get reflected depending upon the color of the material on which it strikes. And the material reflects the light of its own color only, thereby absorbing all the other colored light. So, my questions are:  How would a photon with certain wavelength (say 400 nm) decide to get reflected after striking the material of red color?   What is the actual mechanism behind the reflection of various colored light by the material of different color? DateTime "null" value I've been searching a lot but couldn't find a solution. How do you deal with a DateTime that should be able to contain an uninitialized value (equivalent to null)? I have a class which might have a DateTime property value set or not. I was thinking of initializing the property holder to DateTime.MinValue, which then could easily be checked. I guess this is a quite common question, how do you do that? Can only move object origin in object mode, cant move the mesh I can only move the origin point of the mesh that I selected in object mode, but not the whole mesh Did I set anything up by accident? 'locate' command in terminal. Why is it so fast? I'm looking for an example of a finitely generated module with submodules that are not finitely generated.  I've found  dealing with group (i.e. an example of a finitely generated group with subgroups that are not finitely generated). But I can't figure out whether that question do help to this one.  And I actually want to find a more "module-like" example rather than an example derived from a 'strange' group.  Can you please help? Thank you! Vandermonde Determinant This is an exercise from Ian Stewart's Galois Theory, $3^{rd}$ edition:     If $z_1,z_2,\ldots,z_n$ are distinct complex numbers, show that the determinant $$D=\left|\begin{array}[cccc]  11&amp;1&amp;\cdots&amp;1\\ z_1&amp;z_2&amp;\cdots&amp;z_n\\ z_1^2&amp;z_2^2&amp;\cdots&amp;z_n^2\\ \vdots&amp;\vdots&amp;\ddots&amp;\vdots\\ z_1^{n-1}&amp;z_2^{n-1}&amp;\cdots&amp;z_n^{n-1} \end{array}\right|$$   is nonzero.       Hint: Consider the $z_j$ as independent indeterminates over $\Bbb C$. Then $D$ is a polynomial in the $z_j$, of total degree $0+1+\cdots+(n-1)=\frac{1}{2}n(n-1)$. Moreover, $D$ vanishes whenever $z_j=z_k$ for $k\neq j$, as it then has two identical rows. Therefore $D$ is divisible by $z_j-z_k$ for all $j\neq k$, hence it is divisible by $\prod_{j&lt;k}(z_j-z_k)$. Now compare degrees.   My question is how to do this. I follow the hint and I'm thinking of $D$ as a cofactor expansion; is that the idea? Also, the fact that $D$ vanishes whenever $z_j=z_k$ for $k\neq j$ follows since it would have two identical columns, right? I don't see why $z_j=z_k$ would imply it has two identical rows, as the hint suggests. The fact that it is divisible by $(z_j-z_k)$ is easy since that would make $z_k$ a root for $k=j$, but I'm not quite sure I follow why the degrees would be different. I think the degree of the product would be $1+2+\cdots+(k-1)$, but then add these up for all $k&lt;n$?   I appreciate any clarification that you can provide! Background: I have the opportunity to pursue a Computer Science graduate degree at a well respected program (around top 20). I spoke with the professors at the university and I feel like I am a good fit with their research program. My ultimate pursuits are to complete a PhD in CS. I've done research as an undergraduate and it has only confirmed my notion that I want to pursue a research track career.  More background: I applied to jobs (in case I was rejected to all the programs I applied for) prior to hearing back from my respective graduate programs. I accepted a position for an industry job (this was to secure I wouldn't be both unemployed &amp; not in school).  Dilemma: Turns out my top graduate school is very interested in me, and I'm very interested in them. I would rather go to graduate school than work in industry forever. The industry job pays very well. I am split between A) working for a maximum of 1 year(It would only be 1 year, seriously I do not care about the money enough to work past a year) and B) going straight to graduate school.   My concerns are as follows, if I choose A):    Could I potentially defer my admissions? If I am not allowed to defer my admissions, would I have a good chance of re-applying and being accepted a year later? Would my potential advisers look down on me for deciding to work a year?   I already made my mind up it would be a 1 year gig if I decide A). I know some people say once you make money, you may not be able to readjust to the graduate salary pay. But I don't think that will apply to because I'm going to live very frugally with or without industry pay. Prove that $\overline {A^\complement} = (A°)^\complement $   To show that $\overline {A^\complement} \subseteq  (A°)^\complement$   We first show $A^\complement \subseteq  (A°)^\complement ...(*) $  We know that since $ A°\subseteq A \qquad (*)$ is automatically follows .  The part I didn't understand is the following:     Then we conclude that since $ (A°)^\complement$ is closed    $\therefore \overline {A^\complement} \subseteq  (A°)^\complement$ Spectral radii and norms of similar elements in a C*-algebra: $\|bab^{-1}\|<1$ if $b=(\sum_{n=0}^\infty (a^*)^n a^n)^{1/2}$ Let $A$ be a unital $C^*$-algebra and $a\in A$ such that $r(a) &lt; 1$. Define b  = $(\sum_{n=0}^\infty (a^*)^n a^n)^{1/2}$. We can prove that $b\geq e$ and that $b$ is invertible. I want to show $\| b a b^{-1} \| &lt; 1$.   From the definition of $b$ we see that $a^* b^2 a = b^2-e$ and we know $r(bab^{-1}) = r(a) &lt;1$.   So it suffices to prove $r(b a b^{-1}) = \| b a b^{-1} \|$. It can follow from the fact $c = ba b^{-1}$ is a normal element... I don't know how to prove it (I have tried to compare $c^* c$ and $c c^*$...).    Context: The question appears in Murphy's book, page 74.   I have managed to prove the first part. The second part of the question is to prove $$r(a)= \inf_{c\in Inv(A)}\{\|cac^{-1} \| \}$$ It's easy to see $$r(a) \leq \inf_{c\in Inv(A)}\{\|cac^{-1} \| \}$$ But I can't prove $$r(a) \geq \inf_{c\in Inv(A)}\{\|cac^{-1} \| \}$$ If we have had $r(a) = \|b a b^{-1} \|$ then it was obvious... But this is not true, so how we can prove this inequality? What happens if 2 separate abilities require you to sacrifice a creature? If i have two cards that force opponents to sacrifice every upkeep like for example  "At the beginning of each opponent’s upkeep, Mogis deals 2 damage to that player unless he or she sacrifices a creature."  And  "At the beginning of your upkeep, draw a card unless target opponent sacrifices a creature or pays 3 life."  Does the oppenent have to sacrifice twice? Or if they sacrifice Mogis's ability have they not allowed me to draw from indulgent tormentor? I'm using Terminator version 0.97. Is there a way that I can scroll unlimited? In the current version I only can scroll back limited history