A moderator has deleted one of my answers in two different cases. If a person comes up with two substantially different answers that are based on substantially different viewpoints, is it not appropriate to post them both?  Posting two substantially different answers allows readers to vote on them. Is that not considered acceptable practice in a case where it is not obvious which answer is correct?  In these particular cases I am not certain which answer is correct. The ultimate determination may end up depending on obtaining some more information from the branch of the FAA that is responsible for airspace design, but that hasn't happened yet. At such point as it does, I would expect to be able to delete one of the answers.  Alternatively, some reader may be able to speak authoritatively as to which answer is correct and why, and which is incorrect and why, in a comment. That cannot happen if one answer is deleted.
When is it okay to post two answers to one question?
Merge two unadjacent partitions I have three partitions on my drive, arranged something like the following:   ___________ | 1 |  2 | 3| -------------   I wish to merge partitions 1 and 3.  Is there a way to do this, or do I have to manually "slide" partition 2 over to partition 3, and then merge the newly open space where partition 2 used to be?  Note: I do not have the space to copy partition 2 to partition 3 (2 is 200GB and 3 is 65GB). How to prove this binomial identity $\sum_{r=0}^n {r {n \choose r}} = n2^{n-1}$? I am trying to prove this binomial identity $\sum_{r=0}^n {r {n \choose r}} = n2^{n-1}$ but am not able to think something except induction,which is of-course not necessary (I think) here, so I am inquisitive to prove this in a more general way.  The left side of an identity occurs while solving another problem (concerning binomial theorem) so I am more interested in deriving the right side from the left side, else I have to remember it now onward.  EDIT: I am more interested in an algebraic proof rather than combinatorial argument or something involving calculus (however I liked  and  solution), hence I am removing the combinatorics tag. Can't format my usb drive. I have already tried with mkdosfs and gparted I have a MicroSD card in a USB adapter (which plugs into a USB port on my machine, and acts like a USB flash drive). I was using Unetbootin to make this a bootable USB flash drive with Kubuntu. But I needed to cancel while it was working. So I killed the Unetbootin process from the console.  Since then, I can't format the MicroSD or delete the folder that Kubuntu made. I have also tried mkdosfs, with no success. I can't mount the drive anymore either? What can I do to make this drive usable again?  Trying to create a new partition table in GParted, as described in Eliah Kagan's answer, does not work. It fails with the error message "imposible crear tabla de particiones" ("unable to create a partition table"). English version of Ubuntu with Italian keyboard I want to install Ubuntu in ENGLISH (UK) but I have an ITALIAN keyboard, which has a different layout to the English keyboard. How can I install Ubuntu in English but select an Italian layout for the keyboard. I tried, but it would only allow me to select an English keyboard. Thanks Natural Sort Order in C# Using different delimiters in sed commands and range addresses This is a follow-up to .     When I click a link to an SE site in the Android app, it gives me an "open with" pop-up that has two options:         Chrome   Stack Exchange         I can then choose to open SE posts like this "Just once" or "Always."      The problem is that when I set the SE app to "always," and I click "open in browser,"   Except, the app crashes when trying to open it in browser.  LogCat (just right after selecting "Open in browser")  01-22 18:03:36.354: E/AndroidRuntime(16064): FATAL EXCEPTION: main 01-22 18:03:36.354: E/AndroidRuntime(16064): Process: com.stackexchange.marvin, PID: 16064 01-22 18:03:36.354: E/AndroidRuntime(16064): java.lang.NullPointerException: Attempt to invoke interface method 'int java.util.List.size()' on a null object reference 01-22 18:03:36.354: E/AndroidRuntime(16064):    at com.stackexchange.marvin.utils.Helpers.getNonMarvinViewIntent(Helpers.java:452) 01-22 18:03:36.354: E/AndroidRuntime(16064):    at com.stackexchange.marvin.ui.question.QuestionDialog$1.onClick(QuestionDialog.java:39) 01-22 18:03:36.354: E/AndroidRuntime(16064):    at com.android.internal.app.AlertController$AlertParams$3.onItemClick(AlertController.java:1108) 01-22 18:03:36.354: E/AndroidRuntime(16064):    at android.widget.AdapterView.performItemClick(AdapterView.java:310) 01-22 18:03:36.354: E/AndroidRuntime(16064):    at android.widget.AbsListView.performItemClick(AbsListView.java:1145) 01-22 18:03:36.354: E/AndroidRuntime(16064):    at android.widget.AbsListView$PerformClick.run(AbsListView.java:3066) 01-22 18:03:36.354: E/AndroidRuntime(16064):    at android.widget.AbsListView$3.run(AbsListView.java:3903) 01-22 18:03:36.354: E/AndroidRuntime(16064):    at android.os.Handler.handleCallback(Handler.java:739) 01-22 18:03:36.354: E/AndroidRuntime(16064):    at android.os.Handler.dispatchMessage(Handler.java:95) 01-22 18:03:36.354: E/AndroidRuntime(16064):    at android.os.Looper.loop(Looper.java:148) 01-22 18:03:36.354: E/AndroidRuntime(16064):    at android.app.ActivityThread.main(ActivityThread.java:5417) 01-22 18:03:36.354: E/AndroidRuntime(16064):    at java.lang.reflect.Method.invoke(Native Method) 01-22 18:03:36.354: E/AndroidRuntime(16064):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726) 01-22 18:03:36.354: E/AndroidRuntime(16064):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)   I suspect it's related to , but not sure.  Specs:   Device model: Nexus 5 Android version: Android 6.0.1 SE app version: 1.0.82 (beta) Installed browser: Chrome 47.0.2526.83 (latest at current writing) Let's say we have a Python script my_script.py that does some data processing with Blender. This script accepts some arguments (e.g. arg1 arg2). How can I forward arguments to the script when using it with the CLI?  blender --background --python my_script.py   The only trick I could find was :  echo "arg1 arg2" &gt; my_input.txt &amp;&amp; blender --background --python my_script.py   Is this really the only way to do that?  Update  I found a  on Stack Overflow. Compiling C code in the terminal Is gcc 4.8 or earlier buggy about regular expressions? Usage of "would" and "will" Today I was walking using my iPhone 6S running iOS 9.3 as a pedometer and it shutdown.   When I got home and plugged it in, it said 30% capacity.   That seems strange. I would expect it for 2% or 5% to preserve RAM, but 30%? Maybe there is a setting I don't know about.   My question is: Why does my iPhone power off when the battery is down to 30%?   Edit: this is not a duplicate of the low battery crash as I witnessed the low power shutdown and it was not a crash. Can someone explain __all__ in Python? I have been using Python more and more, and I keep seeing the variable __all__ set in different __init__.py files.  Can someone explain what this does? Merge some tab-delimited files Propane gas fireplace pilot won't light I've asked this question before. Now I've posted some pictures as I can't figure out where I should clean. I don't smell propane. I tired lighting manually with a lighter and nothing. I know to turn the valve on,  rotate the wheel to pilot. Push in and try igniter. It worked fine 6 months ago.   Any suggestions? Prove that $\operatorname{trace}(A) = 0$ if and only if $A^2 = 0$. So i've been working on a Page Object Model framework for a large web application for our current company. It's the first time i've made my own framework and implemented the page object model. Im using Ruby w/Capybara and Selenium-Webdriver for my language/driver of choice.  Currently i've divided each page (or obvious "section of the site") into a class file. This class file has methods for just about everything (or an API of sorts). The problem i've ran into is that I am literally writing a method for every single thing....and i've came across 2 ways people seem to do this:  Lets pretend for a section/page of the site is a widget creation form, the widget has a name/description and some sort of "type" dropdown. Also a save button to save the widget.  Option A (Which is what i've done so far): Make a method for each element (the save button, called save_widget, all the different inputs, etc...)  Option B: Have getter and setter methods for each element, then a larger method which uses these private getter and setter methods.   With Option A my test scripts end up being longer, and honestly not much different than using selenium calls themselves.   Option B would probably call one method (Such as create_widget which would pass in multiple items which that method would call all the smaller getter/setter methods). This would make the test script MUCH shorter and more abstracted. However the getter/setter methods would probably take more actual writing for the page objects themselves (but possibly easier to maintain).  Is there a certain style that favors one over the other? The more I think about it the more Option B seems better...but I wonder if in this case abstraction is a good thing. I am trying to achieve something like this:     This image is linked from .  also provides a solution and seems simpler. Both answers deal with the algorithmicx package however. I am interested in the solution for the algorithm2e package.   I read the documentation of the algorithm2e package but didn't find an answer.   How can I achieve the colored effect?  EDIT:  Here is sample code to create a minimum working example.  \documentclass{article}  \usepackage[ruled]{algorithm2e} % http://www.ctan.org/pkg/algorithm2e  \begin{document}  \begin{algorithm}[h]  \caption{Evolutionary algorithm}   initialize population \;  \For( \emph{Evolutionary loop}){$g := 1$ to $G_{max}$}  {     do things \;     evolve population \;  }  celebrate \; \end{algorithm}  \end{document} Prove that $\phi(n) \geq \sqrt{n}/2$ So I'm trying to prove the following two inequalities: $$\frac{\sqrt{n}}{2} \leq \phi(n) \leq n.$$ The upper bound we get from simply noting that $\phi(n) = n \prod_{p | n}\left( 1 - \frac{1}{p}\right)$ and the fact that $(1 - \frac{1}{p}) \leq 1$. But how can we get the lower bound? I tried using the same expression for $\phi(n)$ but it seems to not really give me the inequality. Can you help? Which is correct?     Everyone were convinced that he would go to the game.   Everyone was convinced that he would go to the game.   I think it's "was", because "everyone" is singular, but I just wanted to check.