How does friction help the car to move forward?
Does a car use friction to move?
If HTML, CSS, and Javascript are client-side, why are they components of a PHP file? Let a,b,c,d be real or complex numbers with absolute value less than $1$. Is the following true:  $$|ab-cd| \leq |a-c| +|b-d|?$$ Adding my launcher to the Unity Launcher automatically. How? Cardinality of equivalence relations on N According to "Moving Around Other Creatures" (PH p. 191 / SRD p. 92):     You can move through a nonhostile creature’s space. [...] another creature’s space is difficult terrain for you.    Whether a creature is a friend or an enemy, you can’t willingly end your move in its space.   So it's possible for Alice to , the only penalty being that the ally's space counts as difficult terrain to enter.  If an enemy adjacent to the ally's space has readied a grapple against Alice and is successful, then Alice (unwillingly) ends her move in her ally's space.  Do allied characters in the same space suffer any negative effect?  Now the rest of Alice's allies do the same thing.   Is there a limit to the number of characters that can be stacked on a space?   What if Alice's ally was the one with the readied grapple?  Can you stack an ally on your space by readying a grapple to prevent them from leaving? Reflection is quad dependent and looks non realistic Im rendering varous objects with a Sharp glossy effect but the reflections are quad dependent on the object (image below), meaning they behave separately within every quad making it look 8bit-like. Can anyone tell me why this happens?. (Im pretty sure subdividing would fix it but I want to know why I cant have a low poly object reflecting normaly.  The object has 2 modifiers: Subdiv Surface and Solidify. (Perhaps the Subdiv is causing it?). Help me you Blender savys I dont have a powerful CPU to test and test within every render would take me hours and hours.  Image: How do I add a DNS server via resolv.conf? Is /etc/resolv.conf useless in  (Precise Pangolin)?  I see that the DNS server information is stored in  now. The nmcli command line tool can list that for you.  If I want to add one more  server, will adding it to /etc/resolv.conf by using the resolvconf package help? Is there any difference between "word-for-word translation" and "word-by-word translation" and is the latter actually valid? First off, some data: According to COCA word-for-word has 60 usages, 3 of them are &quot;word-for-word translation&quot;. Word-by-word has 26 usages, none of them are &quot;word-by-word translation&quot; (but some with &quot;transcription&quot;). The definition of word-for-word:  : In exactly the same or, when translated, exactly equivalent words : being in or following the exact words, verbatim : one word at a time, without regard for the sense of the whole  Only the last dictionary contains a definition for word-by-word, too:  : one word at a time  The definitions given by The Free Dictionary are, obviously, identical to each other. Google hits: Word-for-word ~21m Word-for-word translation ~318k Word-by-word ~3.8m Word-by-word translation ~95k According to usages and dictionaries word-by-word is, at least, less popular. And assuming that there may be a lot of usages from non-natives among the Google hits, this could be an indicator for word-by-word being even utterly wrong. In another forum I found the following :  When I translate something &quot;literally,&quot; (wörtlich) it still follows the main rules of the language I'm translating into. What you mean is &quot;word-by-word&quot; (wortwörtlich) to me.  I assume that this was written by a German but I don't know it. However, if this would be true a &quot;word-by-word translation&quot; would be a translation where I keep, for instance, the order of the words, disregarding if it makes sense in the target language. Some examples:  Original: word-by-word Word-by-word translation: Wort bei Wort (That's a terrible translation!) Original: It is critical to know... Word-by-word translation: Es ist kritisch zu wissen... (That's a terrible translation!) Original: Ich glaub, ich spinne. Word-by-word translation: I think I spider. (I guess only Germans understand this.)  A &quot;word-for-word translation&quot;, however, would be an attempt to keep the word-choice as close as possible but following the rules of the target language (e.g. order of words) and also considering if the statement still makes sense in the other language. Here are better translations for the examples above:  Wort für Wort Es ist wichtig zu wissen... I think, I'm going nuts. (Actually, this is not a word-for-word translation but rather a .)  So, my questions again:  As neither Oxford nor Merriam-Webster have any entries for word-by-word in their dictionaries: is word-by-word actually valid? If yes, is there any difference between &quot;word-by-word translation&quot; and &quot;word-for-word translation&quot;? If yes again, what is it specifically? Is 'acronymise/ze' a word? Is it used only colloquially, if at all? I just sent a text to a friend, who didn't understand an acronym I used for a game:      "Ah, I said it in a previous text so thought it was ok to abbreviate   it."   Though, since it was an acronym I had created, could I have used the word 'acronymise/ze' to be more specific?   I'm pretty sure it isn't a (formally used) word, but I wondered, as you often refer to acronyms specifically as acronyms, rather than abbreviations. Can you be more specific with a verb, too?  It sounds too odd to me, so I'm guessing generally no. But I wondered—so perhaps I'm wrong. Or half wrong. Image Alpha Background Renders Black when using "Import Images as Planes" I must be missing something here.  I'm doing an extremely simple Import Image as Plane using the AddOn and the imported image has an alpha background but it renders (and even previews in the material preview) as black where the alpha background should be.  When I import, I select Emission &amp; Transparent so the material setup is automatic.  I've read similar issues but people are typically missing the transparent node and connecting the Alpha channel from the image into the Mix Node factor.  But this is all here.  I must be missing something really stupid but I've wasted so much time trying to fix this thing.  Any help would be greatly appreciated.  Not sure if it matters but I'm using 2.74 RC2.  Many thanks!  I created this dummy blend file to test outside my project but problem still exists.  Here is the simple .blend file: Showing group with $p^2$ elements is Abelian I have a group $G$ with $p^2$ elements, where $p$ is a prime number. Some (potentially) useful preliminary information I have is that there are exactly $p+1$ subgroups with $p$ elements, and with that I was able to show $G$ has a normal subgroup $N$ with $p$ elements.   My problem is showing that $G$ is abelian, and I would be glad if someone could show me how.   I had two potential approaches in mind and I would prefer if one of these were used (especially the second one).   First: The center $Z(G)$ is a normal subgroup of $G$ so by Langrange's theorem, if $Z(G)$ has anything other than the identity, it's size is either $p$ or $p^2$. If $p^2$ then $Z(G)=G$ and we are done. If $Z(G)=p$ then the quotient group of $G$ factored out by $Z(G)$ has $p$ elements, so it is cylic and I can prove from there that this implies $G$ is abelian. So can we show theres something other than the identity in the center of $G$?  Second: I list out the elements of some other subgroup $H$ with $p$ elements such that the intersection of $H$ and $N$ is only the identity (if any more, due to prime order the intersected elements would generate the entire subgroups). Let $N$ be generated by $a$ and $H$ be generated by $b$. We can show $NK= G$, i.e every element in G can be wrriten like $a^k b^l $. So for this method, we just need to show $ab=ba$ (remember, these are not general elements in the set, but the generators of $N$ and $H$).   Do any of these methods seem viable? I understand one can give very strong theorems using Sylow theorems and related facts, but I am looking for an elementary solution (no Sylow theorems, facts about p-groups, centrailzers) but definitions of centres and normalizers is fine. Using first person or third person in papers? Are there written or unwritten rules for avoiding the use of first-person while writing research papers? I was advised at the beginning of my grad school to avoid use of first person - but I still don't know why I should do this.  I have seen that, at many places, authors refer to themselves are "the authors" and not "we". At the same time, I have also seen use of first-person to a good extent.    Do these things differ in different Journals and Conferences (and in different disciplines as well - mine happens to be CS)? Potential difference across a zero resistance wire Register On-Click Event with jQuery - Not Firing finding $\int_0^\infty \dfrac{dx}{1+x^4}$ through complex analysis Functions which are Continuous, but not Bicontinuous What are some examples of functions which are continuous, but whose inverse is not continuous?  nb: I changed the question after a few comments, so some of the below no longer make sense. Sorry. Should there be a comma in 'a 30-day, money-back guarantee'? How does the size of insert affects the rate of Homologous Recombination in yeast? When performing genetic knockouts in yeast using homologous recombination to replace a target gene sequence via a vector DNA, does the region between the flanking regions in the vector have to be the same length as the site of recombination in the host cell's gene? When is partial differentiation commutitive Consider a function: $$f:\mathbb R ^2\to\mathbb R $$ when does $$\dfrac {\partial f(x,t)}{\partial t\partial x}=\dfrac {\partial f(x,t)}{\partial x\partial t}$$  Thinking about it in terms of the limit definition of derivative,  and thinking about it as taking slices of surfaces and measuring the slope on the edge, seems to be giving me the feeling that answer is always.  However I have some memories of there being requirements like piecewise continuous, and smooth.   What is the full set of conditions? Naive visualization of space-time curvature