Which one is more acceptable?     1. Each boy and each girl has done his duty.      2. Each boy and each girl has done his or her duty.      3. Each boy and each girl has done their duty.   Edit: Here is what I think.  I think (1) isn't acceptable because 'his' is in masculine gender, which doesn't fit the noun 'girl'. (3) isn't acceptable because the verb 'has' is singular but the pronoun 'their' is plural. (2) is ok but the expression "his or her" looks awkward.
When I start a sentence with words like "someone" or "somebody", I don't know how to choose the right pronoun at the end of the sentence.  Examples:      If anybody asks you about the money, tell (Him - Her - It - Them) that it is in my bank account.     I felt that somebody was in the garden but I did not see (Him - Her - It - Them).     Speaker 1: A friend of mine helped me a lot.      Speaker 2: You should thank (Him - Her - It - Them).     Congratulations on your new baby! What's (His - Her - Its - Their) name?    Those are the cases or situations that I can think of. If you have any other different situations, please let me know.
File list command line (hidden and subfolders) Why cant I navigate to lightning component in communities? Im on a lightning community, i have a lightning component and i want to open another component with this code:  navigateToMyComponent : function(component, event, helper) {     console.log('1');     var evt = $A.get("e.force:navigateToComponent");     console.log('2');     evt.setParams({         componentDef : "c:CompetenciaComponent"     });     console.log('3');     evt.fire();     console.log('4'); }   this its the console log:   NOTHINGS HAPPEND AND I DONT KNOW WHY Why does ice make such peculiar sounds? I've come across a couple of videos where some interesting sounds are produced using ice.  (Click on the images to see the video.)      Here, they drop a block of ice into a deep crevice and as the block falls, you can hear some strange sounds. These sounds remind me of some sound effects in old cartoons and sci-fi movies. The pitch of the sounds start high and end up low. Is this some kind of doppler effect?      Here, there's a man performing 'nordic skating', making the same sounds as he skates on top of a thin ice sheet. Maybe they are caused by the cracking ice. But why does that sound like this?    There are some other videos too, where they skip stones on frozen lakes.    Here the ice makes some high-frequency sounds which correspond to the chirping of birds.  What are these sounds and why do they sound the way they sound? If a prime divides a product then it must divide a factor of the product [Euclid's Lemma] We have $q, p$ prime and $tq = (p-1)(p+1)$ for some positive integer $t$. The book I'm reading says that because $q$ is prime, it divides $p-1$ or $p+1$.   Question: Why exactly does it matter that $q$ is prime here? Let $G(r, n)$ be the Grassmannian of the set of all $r$-planes in a $n$-dim vector space. How to show that the cohomology of a Grassmannian has a basis consisting of the equivalent classes represented by Schubert cycles? I am confused since I don't know how to compute the cohomology of a variety (how to construct the co-chain complex). I am really appreciate if you can compute the cohomology of, for example, $G(2,4)$ and show that it has a basis consisting of the equivalent classes represented by Schubert cycles. What would be a good term for continuous testing post-deployment? I'm thinking of live production sites here, where there is a continuous community or much content being updated, sort of like a newspaper site or community site (the one I work at is a healthcare improvement company) and we have news articles, programs and so on.  While the underlying code is tested and released there are often production issues that come up, maybe certain pages stop working, style sheets suddenly don't appear like they did due to a service patch or some tweak done to improve production security or performance.  There is Acceptance Testing for when a deployment goes out to make sure things work right, Regression Testing to make sure nothing has been broken since previous releases.  Considering we've done these types of tests and things are working fine what would you call testing, or checking, the site to make sure things still work fine?  To be sure new pages are being crawled for search indexing?  To check that newly added pages are using plug-ins correctly?  Or so on.  My manager and I were discussing some issues that have cropped up and decided we needed to do something like this, but then to sort of note it in our status reports we didn't really have a name for it.  Anyone done this and have a term that might be good?  Or would you consider it covered by something like Continuous Acceptance Testing or some such term? Proof of $\lim_{n\to \infty} \sqrt[n]{n}=1$ Thomson et al. provide a proof that $\lim_{n\rightarrow \infty} \sqrt[n]{n}=1$ in . It has to do with using an inequality that relies on the binomial theorem:  I have an alternative proof that I know (from elsewhere) as follows.  Proof. \begin{align} \lim_{n\rightarrow \infty} \frac{ \log n}{n} = 0 \end{align} Then using this, I can instead prove: \begin{align} \lim_{n\rightarrow \infty} \sqrt[n]{n} &amp;= \lim_{n\rightarrow \infty} \exp{\frac{ \log n}{n}} \newline &amp; = \exp{0} \newline &amp; = 1 \end{align}  On the one hand, it seems like a valid proof to me. On the other hand, I know I should be careful with infinite sequences. The step I'm most unsure of is: \begin{align} \lim_{n\rightarrow \infty} \sqrt[n]{n} = \lim_{n\rightarrow \infty} \exp{\frac{ \log n}{n}} \end{align} I know such an identity would hold for bounded $n$ but I'm not sure I can use this identity when $n\rightarrow \infty$. Question: If I am correct, then would there be any cases where I would be wrong? Specifically, given any sequence $x_n$, can I always assume: \begin{align} \lim_{n\rightarrow \infty} x_n = \lim_{n\rightarrow \infty} \exp(\log x_n) \end{align} Or are there sequences that invalidate that identity?  (Edited to expand the last question) given any sequence $x_n$, can I always assume: \begin{align} \lim_{n\rightarrow \infty} x_n &amp;=  \exp(\log \lim_{n\rightarrow \infty} x_n) \newline &amp;=  \exp(\lim_{n\rightarrow \infty} \log x_n) \newline &amp;=  \lim_{n\rightarrow \infty} \exp( \log x_n) \end{align} Or are there sequences that invalidate any of the above identities? (Edited to repurpose this question). Please also feel free to add different proofs of $\lim_{n\rightarrow \infty} \sqrt[n]{n}=1$. What is the best place for storing binary files that are related to data in your database? Should you:   Store in the database with a blob Store on the filesystem with a link in the database Store in the filesystem but rename to a hash of the contents and store the hash on the database Something I've not thought of   The advantages of (1) are (among others) that atomicity of transactions is preserved. The cost is that you might dramatically increase storage (and associated streaming/backup) requirements  The goal of (3) is to preserve atomicity to some degree - if you can enforce that the filesystem you are writing to does not allow files to be changed or deleted, and always has the correct hash as filename. The idea would be to write the file to the filesystem before permitting the insert/update referencing the hash - if this transaction fails after the filesystem write but before the database DML, that is fine because the filesystem is 'faking' being the repository of all possible files and hashes - it doesn't matter if there are some files in there that are not being pointed to (and you could clean them up periodically if you are careful)  EDIT:  It looks like some RDBMSs have this covered in their individual ways - I'd be interested to know how others do it - and particularly in a solution for postgres Saving Photoshop multilayer file to PDF without layers size difference Why is it that when I save a file that has many, many layers to a PDF without layers as a copy that the file size is larger than flattening the layers and then saving the file as a copy to PDF? 19Mb vs. 5Mb?? Wouldn't saving a file without layers be the same as flattening the layers and then saving the file?? Can anyone explain this? I just found http://programmingfaq.w3ec.com/faq/4761/whats-the-hi-lo-algorithm which has an exact copy of this Stack Overflow question, , with all its answers and no difference in a single character. There is no reference to Stack Overflow.  Is this legal, or at least tolerated? Is this impertinent theft of information? I just can't see any sense in copying whole pages, particularly when not referencing the source. Some common problems with displaying routes created from street data, such as bus routes, include:   Routes may overlap themselves, such as when a route takes the same road in opposite directions Routes may overlap other routes that take the same street. Routes are often overly detailed, or "noisy", owing to their derivation from street data. Indicating a route's direction unambiguously without overloading it with arrows can be a challenge.   What are some techniques for dealing with these issues in order to create a practical and usable route map, such as this ? Do you know of any such public transport maps that were produced by automatic techniques rather than manual illustration/digitization?  Specifically I am using ArcGIS 10, but solutions involving other software are welcome as well.  One technique I have had some success with for dealing with 1) is using ArcMap's  with a negative offset -- assuming the lines are oriented in the direction of travel, this will offset the lines such that the right and left-hand sides are distinct and oriented as you would expect (at least for  countries, for left-hand traffic countries one would use a positive offset). However the result tends to be a bit wonky around turns, interchanges and and U-turns, and is inflexible when dealing with multiple routes.  Another possibility that I am not very familiar with but which seems promising is  -- however, I have not had much luck in finding examples of using representations for transportation maps and whether it might fit the bill. I have an empty file (only zeroes are in it) of size 9,0KB and I need to write another file (with size 1,1KB) to it, but the first file must not lose its size or the rest of its contents. So if the whole file is 00000000000000... now, I need to write second file in it and leave the zeroes as they are. I have tried to use dd, but I haven't succeed - file resizes.  dd if=out/one.img of=out/go.img   Does anybody know how can I do it? Meaning of "over in" I read this sentence in a book:     I just took part in a study over in the Psychology Department.   Why do we add over in front of in the here? Properties of $\liminf$ and $\limsup$ of sum of sequences: $\limsup s_n + \liminf t_n \leq \limsup (s_n + t_n) \leq \limsup s_n + \limsup t_n$ Let $\{s_n\}$ and $\{t_n\}$ be sequences.  I've noticed this inequality in a few analysis textbooks that I have come across, so I've started to think this can't be a typo:  $\limsup\limits_{n \rightarrow \infty} s_n + \liminf\limits_{n \rightarrow \infty} t_n \leq \limsup\limits_{n \rightarrow \infty} (s_n + t_n) \leq \limsup\limits_{n \rightarrow \infty} s_n + \limsup\limits_{n \rightarrow \infty} t_n$.  I understand the right two-thirds of the equation, and can prove it.  I'm stuck on the far-left third.  I don't understand how that is true. Composition of a harmonic function with a holomorphic function is still harmonic If $f$ is a harmonic function in a domain $D \subset \mathbb{C}$, and $g$ is a conformal mapping of a domain $D_0$ onto $D$, is $f \circ g$ harmonic in $D_0$?   I noticed this question while reading several pdf of lecture notes, and I'm having trouble figuring it out. Can anyone help?  Thank you so much! 1.7.4 Problem with mobs spawning I have just updated to Minecraft 1.7.4 and now all of a sudden there are barely any mobs spawning.  I checked to make sure that I was in normal difficult and I saw 1 creeper but that is all.  Also I tried different difficulties. Another thing - mobs seem to to spawn normally in the nether and all other mobs except aggressive mobs spawn like they should.  Please if you know how to fix this, please help! How to add new element to Varargs? If $U$ is unitary operator then spectrum $\sigma(U)$ is contained inside the unit circle In a Hilbert space, let $U$ be a continuous operator which it unitary. Prove $\sigma (U)\subseteq \Bbb{S}^1$.   It is important for me to know how I am doing, and I didn't come by a clear explanation so it would be appreciated to have your correcting and guiding.  Attempt: $U^{*}U=UU^{*}=I$ and therefore $U^{-1}=U$. I have $$ \| U x \|^2 = \langle U x, U x \rangle = \langle U^* U x, x \rangle = \langle x, x \rangle = \|x\|^2 $$ and the same goes for $U^*$ and therefore $\| U \| = \| U^{-1} \| = 1$.   Looking at $U-\lambda$ I can take $$ -\lambda U(U^{-1}-{1\over \lambda}I) =U-\lambda I. $$ Clearly, for $\lambda \ne 0$, $-\lambda U$ is defined and is a linear operator. $(U^{-1}-{1\over \lambda}I)$ is invertible if $|\lambda|\ge 1$ and therefore $\sigma (A^{-1})=\sigma (A)\subseteq \{|z|\le1\}$. But from the RHS, $U-\lambda I$ is invertible if $|\lambda|\le 1$ and therefore $\sigma(A)\subseteq \Bbb{S}^1$. I have noticed my claims tend to have holes in them many times which I cannot spot. If it is substantially true, how can I make sure it is completely formal? How to disable captive portal detection? How to remove exclamation mark on Wi-Fi or signal icon in Lollipop? Reading Excel files from C#