My grammar book suggests that when using words like just, that you should “always” use present perfect. So the correct form should be I've just arrived according to my book.  Is this true?  I ask because I see a whole lot of people using I just arrived all over the place.  I therefore cannot help but wonder whether this is an incorrect form that is somehow nonetheless in wide use by native speakers, or whether it's also a correct form just with a subtly different meaning.
Lyircs of Free by Natalia Kills:     I'm free      I just spent all my money       but I rocked that like it don't cost a thing   Shouldn't it be "I've just spent all my money"? As far as I remember, our English told us to use Present Prefect in such case because of the just.
Google Spreadsheets: IF not working I have problems with my IF command in Google Sheets. If gives #ERROR! all the time. See this simple test:    Not even if I put in the number directly and avoid references:    Am I using the IF wrong? Or what could such a problem be? This example is from a new document. Sort arrays of primitive types in descending order How can I remove fonts that I never use, from libreoffice and linux in general? There are a lot of extra fonts that all seem to look alike and just annoy me in the drop down list. Is there anyway I can erase them from the system? Increasing post view count automatically Replacing ArcPy with ArcGIS API for Python? Today I found out about the . I was wondering if you could use this to (eventually) replace ArcPy?  Recently I have been doing analyses that require cloud based solutions. When using AWS, Docker and Jupyter it is very convenient to stick with a Unix based OS such as Ubuntu. However, the Unix alternatives for ArcGIS have their own limitations as well such as the always hard to install python bindings for the  GDAL library. ArcGIS for Python operates cross platform.  Perhaps there are the things I should and should not expect from the ArcGIS API for Python.  Perhaps Arcpy is going to disappear altogether. Let $Q_8$ be the quaternion group. Show that $G/Z$ can never be isomorphic to $Q_8$, where $Z$ is the center of $G$. Hint: if $G/Z\cong Q_8$, show that $G$ has two abelian subgroups of index $2$.  I'm trying to prove the hint by looking at the canonical homomorphism $\pi:G\rightarrow G/Z$. Well, $Q_8$ has some abelian subgroups of index $2$, such as $H=\{1,-1,i,-i\}$, but that doesn't seem to map to abelian subgroups of index $2$ of $G$. (We know that $\pi(ab)=\pi(a)\pi(b)=\pi(b)\pi(a)=\pi(ba)$ for $a,b$ in $\pi^{-1}(H)$, but that only yields $aba^{-1}b^{-1}\in Z$, not $aba^{-1}b^{-1}=1$.) A sine integral $\int_0^{\infty} \left(\frac{\sin x }{x }\right)^n\,\mathrm{d}x$ The following question comes from   post $$\int_0^{\infty} \left(\frac{\sin x }{x }\right)^n\,\mathrm{d}x$$ but now I'd be curious to know how to deal with it by methods of complex analysis. Some suggestions, hints? Thanks!!!  Sis. Short Story: Army investigates barrier and house I am trying to identify the author and title of a short story with the following plot.  A scientist narrates a story where s/he is called in to help the army investigate an unexplained phenomena.  The army has cordoned off an area where a prairie home has appeared. It is surrounded by a dome that allows things to enter but not to leave. Briefing the scientist, the Army explains that it appears that it is a family of five with mother, father, son, daughter, and grandfather. They look completely normal and live an idyllic life of the 40s or 50s.  They continue to send probes in to investigate the dome and its proprieties. Not sure if this a time anomaly or another dimension.  An Army lieutenant, so enamored by their life runs through the barrier to join the family. The Family faces split into an unnaturally wide smile full of sharp teeth runs towards him and tears him to pieces &amp; eats him. The grandfather then looks up acts as if he can see the forces gathered outside the barrier. He then retrieves a book and it looks as if he reads it out loud and the house and barrier disappear. The narrator worries that the aliens will return. Still alive, still alive after kill -9 / SIGKILL An apache2 process got stuck on my server and caused problems with other services. (original problem: kerneloops after USB hardware disconnect)   root@server:~# ps aux | grep apache2 | grep -v grep www-data 12917  0.0  0.1 412148 16156 ?        D    Jun27   0:00 /usr/sbin/apache2 -k start   Naturally, I killd it. it's still alive. so I kill -9d it. It's still "alive".  Now this is where the question gets serverfault/unix&amp;linux-worthy: Is there a way to get port 443 back without doing the obvious thing: rebooting? Iptables is installed.  Update: I could not resolve the Problem withouth rebooting. The general approach (use lsof or /proc/$PID/fd to find out which and get rid of that drive) as described here and in the "duplicate" could well have worked if not for additional (probably) hardware defects. What is this electronics symbol (four triangles?) Stance on repost question instead of editing to invalidate answers? Regarding , made by me, and general questions in this matter. I did receive decent answers on the question that was asked, but it wasn't asked clear enough by me I now see. I do not want to invalidate the answers by completely restructuring the question. Should one post a new question ignoring the other? or Should one refer to their old post and writing a short &quot;because x I reposted this...&quot;? What lifetime can be expected of the typical hard disk? Or are there big differences between different types? And does it make a difference if it is used heavily instead of never being connected to system (for example serving as a backup medium)? Same script opened in three different ways produces three different results. Why? I have a sample script (credit goes to ):  #!/bin/bash cat &lt;(cat /etc/lsb-release)   I save this script as somename.sh in my home directory.  Now, I try to open this file in three different ways:  sh somename.sh  bash somename.sh  ./somename.sh   So, I have two questions:   Why are the outputs for the above commands different though they are running the same script?   sh produces a Syntax error bash outputs the desired result ./ gives a Permission Denied error  Why is it necessary to give the script executable permission only when running the script using ./ and not necessary in the other cases?   Thanks in advance!  EDIT: The first part might be similar to the  linked one but, I did have a second question too. How many String objects will be created when using a plus sign? Let $\mathbb{F}$ be a finite field.  Let $a_1,\dots,a_n \in \mathbb{F}$ be given.  I want to know whether there exists $x_1,\dots,x_n \in \mathbb{F}$ such that  $$a_1 x_1^2 + a_2 x_2^2 + \dots + a_n x_n^2 = 1.$$  My question: Can we characterize when this equation has a solution, i.e., by some criterion on $a_1,\dots,a_n$?  Is there a clean characterization, in terms of $a_1,\dots,a_n$ and the properties of $\mathbb{F}$?    Here's what I can see immediately.  First, if $n=1$, there is an easy answer (the equation has a solution iff $a_1$ is a square in $\mathbb{F}$).  Second, if any $a_i$ is a square in $\mathbb{F}$, the equation has a solution (set all other $x_j$'s to $0$), so we can assume that all the $a_i$'s are non-squares and that $n \ge 2$.  Third, if $-1$ is a square in $\mathbb{F}$, then the equation has a solution: we can take $x_2 =  \sqrt{-a_1/a_2} \cdot x_1$.  But what about the case where $-1$ is a non-square in $\mathbb{F}$?  Is it always guaranteed to have a solution in this case? Bash Script if condition is always true I would like to see a breakdown of reputation by post type on the user summary page.    This would help show, at a glance, how much someone actually knows vs. how good they are at asking questions.  For instance:     Reputation from Questions - 10,015 from 1024 posts   Reputation from Answers - 110 from 11 posts   Reputation from Edits - 400 from 1000 edits     I would take any answers the above person gave me with a grain of salt instead of assuming they were knowledgeable because they have 10k rep.  We already have a multitude of other readouts on the new page, so this shouldn't up the clutter factor too much either. Find All Solutions to System of Congruence $$ \begin{cases} x\equiv 2 \pmod{3}\\ x\equiv 1 \pmod{4}\\ x\equiv 3 \pmod{5} \end{cases} $$  $ n_1=3\\ n_2=4\\ n_3=5\\ N=n_1 * n_2 * n_3 =60\\ m_1 = 60/3 = 20\\ m_2 = 60/4 = 15\\ m_3 = 60/5 = 12\\ gcd(20,3)=1=-20*1+3*7\\ gcd(15,4)=1=-15*1+4*4\\ gcd(12,5)=1=12*3-5*7\\ x=-20*2-15*1+12*3\equiv -19 \equiv 41 \pmod{60}\\ $  The above is what I've tried so far. Can someone tell me where I'm going wrong? It's my first time doing this and looking at the explanation and examples for the Chinese Remainder Theorem makes my head want to explode. Good Number Theory books to start with? I'm in Grade 11. I'm interested in elementary number theory and would like properly study it. I'm not intending to enter any competitions. If random variables are drawn from an identical distribution, why doesn't this guarantee they are independent?