Given two points on a manifold, is there a chart containing both?
For any smooth manifold, is it true that for any two points on the manifold, there exists a chart that covers the two points?
I accidentally set an object as camera, how do I undo this? Output the common lines (similarities) of two text files (the opposite of diff)? Diff is a great tool to display the changes between two files. But how to display the similarities of two text files (while ignoring the differences)?  I.e. sample input:  a: Foo Bar X Hello World 42  b: Foo Baz Hello World 23   Pseudo output (something like this):  @@ 2,3 =Hello World   Just sorting both files and using comm is not enough, because in that case the line information is lost. Boot Error - ACPI PCC Probe Failed ACPI PCC Probe Failed is the error that pops up instead of the default GRUB loader after I updated my kernel to 3.19.  I searched around and couldn't find much information except that it is a known error and it is registered in kernel.org's launchpad . My question is, is anyone else facing it?, what are the impacts of this? And if only an update in the future can fix it, any suggestions or safety tips till then? I washed and dried my passport by mistake, do I need a new one? Around two years ago I washed and dried my passport by mistake at the laundry room. My ID, my old US student visa and my stamps from european countries are still readable but the pages are not "flat" anymore and the front cover is kind of erasing (some parts of the Brazil symbol is gone).   In April I'll travel to US for a conference, I'll need to get a new US visa (B1/tourism visa) but I'm worried if my passport is not "good to go" anymore because it was "washed and dried". Apparently there is an electronic chip in it and I don't know if it is still working.  Should I get a new passport or can I save some money and time and use this one? It expires only in 2019. $E(|X-Y|)$ for $X$, $Y$ i.i.d and uniform on $[0,1]$ What is $E|X-Y|$ when $X$, $Y$ are i.i.d and uniform on $[0,1]$?   I want to do something like   $$ E(|X-Y|)=\iint_{x&gt;y}(x-y)\;dxdy+\iint_{y&gt;x}(y-x)\;dxdy=2\iint_{x&gt;y} (x-y)\;dxdy $$  But am not sure how to solve that last double integral or if this setup is right. drush/drush dev-master requires codegyre/robo ~1.0.0-beta1 I'm transitioning a Drupal 6 site to Drupal 8.1 so following the official instructions, I set up a new install in its own directory. Since this is only one site, I followed the instructions to put my database credentials in sites/default/default.settings.php after the declaration of the $databases array.  Running drush --status returns the following.  Drush version          :  8.1-dev                                           Drush temp directory   :  /tmp                                              Drush configuration    :                                                    Drush alias files      :                                                    Drupal root            :  /media/psf/Home/apps/newp                         Drupal Settings File   :  MISSING   Since this Drupal is 8.1-dev that must mean I need to upgrade it. Since this is a global install using Composer, I run composer global update.     Your requirements could not be resolved to an installable set of   packages drush/drush dev-master requires codegyre/robo ~1.0.0-beta1   Checking the drush-ops page on github doesn't show any anomalies like this nor my Google search.   What am I overlooking? how to make a regex string reject a blank field Can I visit the US twice within a 90 day period under the Visa Waiver Programme? 2nd time is only to transfer (change terminal, not airside). How to make a redstone clock that I can turn on/off with a lever? I want to create a Redstone clock that can be enabled and disabled with a lever permanently placed down. he or she vs their when using 'one' as a pronoun Mindfulness allows one to cope with their daily challenges.   Is "one" correct with "their" here?  I want to know if it is okay to user their (instead of he or she) when using 'one' as a pronoun. What pressure should I run my Road Bike tyres at? There's a question for mountain bike tyres but I can't seem to find anything on here for road bikes. At the moment I'm running at around 90psi. Is that too much? too little?  Also, am I more likely to get punctures running at higher pressure?  I seem to be getting a lot lately. I'm about to start exploring the world of long exposure shots, using my Canon EOS M. The camera has a standard max exposure time of 30 seconds, but in bulb mode I can keep the shutter open indefinitely (using a wireless remote to control the shutter.)  How long can I leave the shutter open without running the risk of prolonged exposure to light damaging my sensor?  For the purposes of this question assume I'm shooting in summer daylight, so that we can go by the worst case. If $X$ and $Y$ are sets, their cartesian product $X\times Y$ is a set. In ZFC set theory, every element object is a set. We know or feel that if $X$ and $Y$ are sets, their cartesian product $X\times Y$ is a set.  My question is: Why if $X$ and $Y$ are sets, their cartesian product $X\times Y$ is a set? 80s-90s anime (movie or series) in which an armored girl exchanges age with a dying man on a beach Why does switching to the tty give me a blank screen? After booting to the GUI in 12.04, I attempt to move to the virtual terminal (or shell, or tty) via Ctrl-Alt-F1 (F1 through F6), and the screen remains blank. I have tried all 6 tty instances and the results are the same. Ctrl-alt-F7 brings me back to the GUI without a problem. Any thoughts? We had a small widget that allowed customers to share records that were set to a private sharing model in our community. Everything was rather simple and it would simply allow them to select users that were visible via Sharing Sets and create an __Share record in APEX.  I've been reported recently that an error is thrown but only on the community side of things. Nothing seems to be working where it was working. We are using    Customer Community Plus licenses.  The error being thrown is : System.TypeException: DML operation INSERT not allowed on &lt;Object&gt;__Share which seemed to indicate access not available on the object. That seems odd because they are able to interact with the object just fine in order to create/edit/delete them.  I looked up the Sharing Model (its private both internally and externally), I looked at the profile and their access and the sharing sets in the community. Like I said, they seem to interact fine with the objects when it comes to seeing the records and their right.  Additionally, standard license users can use the component fine and also share with community users without a problem. They also see the records as expected.  Am I missing an update or something that seem to make it so this doesn't work anymore? Anyone having trouble with this or encountered the same problem? Subdividing a beveled mesh creates new vertices in wrong places headed or heading, started or starting? Consider:  Two units are headed your way. Two units are heading your way. Don't get me started! Don't get me starting!  Is there any difference in meaning? And I don't see why passive voice is used here. I would think they have similar meaning here. Help me to clarify! Sequence of tenses for facts irrelevant of the moment of speech Let's consider two sentences:     (1) I suggested that the word zeitgeist was of German origin.   (2) The lecturer said the Pluto's orbital period is more than 200 years.   In both cases, the facts are always valid and  irrelevant of the moment of speech and context. I've heard sequence of tenses is not required in such cases. Are past and present tenses interchangeable in both of them? Would it be correct to say:     (1) I suggested that the word zeitgeist is of German origin.   (2) The lecturer said the Pluto's orbital period was more than 200 years. Disable Mac startup sound Anyone know how to disable that cheesy startup sound when I power on my Mac?  If it makes a difference, I'm running Mac OS X 10.6.