I'm going on holiday soon and we planned to take a USB hub to charge all of our devices rather than take several wall adapters, however when I checked that my 7" Samsung Galaxy Tab 3 would charge, I found that it didn't. After investigating, I found that my iPad charger wouldn't charge it either and in fact the only that would charge it was the USB wall adapter that came in the box with the tablet, even though the port on the USB hub and the iPad charger are rated at 2.1 A (5 V).  When I plug the tablet into to a non-Samsung adapter powered off however, the screen flashes lighter and darker but nothing else happens which seems odd behavior to me.  What is the reason it will not charge by any other means, and is there a solution?
The USB has various purposes for data transfer, movement of input and output signals for hardware like connecting an Android device to another Display screen (USB on the go), charging the device etc.(during a device charge the voltage drawn from the USB is same irrespective of the device or OEM then Why are two USB Cables different ?  A USB of one manufacturer may not be supporting another manufacturer. We get problems if we do connect them like      or
We have the following points: $$ (0,0)(1,51.8)(1.9,101.3)(2.8,148.4)(3.7,201.5)(4.7,251.1)  \\ (5.6,302.3)(6.6,350.9)(7.5,397.1)(8.5,452.5)(9.3,496.3) $$ How can we find the best fitting line $y=ax$ through the points? My calculator has the option to find the best fitting line $y=ax+b$ through these points, which is:  $$y = 53.28x + 0.37$$  How can I find the best fitting $y=ax$? It seems to me we can't just remove the $0.37$ without compensating in the $a$? MariaDB won't start on Ubuntu: Can't lock aria control file Misplaced/Overlapping Navigation Item Text on iOS 10 The bug displayed in the attached screenshot occurs consistently for me while running the developer beta of iOS 10 using v1.5.2 of the Stack Exchange app on an iPhone 6.  I was able to recreate this by simply tapping on any question or answer in my feed with a long title. This doesn't appear to be a bug with iOS 10 itself since I haven't seen it in other apps, but I could be wrong. I just came across this idiom in some open-source Python, and I choked on my drink.  Rather than:  if isUp:     return "Up" else:     return "Down"   or even:  return "Up" if isUp else "Down"   the code read:  return isUp and "Up" or "Down"   I can see this is the same result, but is this a typical idiom in Python? If so, is it some performance hack that runs fast? Or is it just a once-off that needs a code review? Can someone please give me a tip how to show that for distinct prime $p,q$ that $\mathbb{Q}(\sqrt{p},\sqrt[3]{q})=\mathbb{Q}(\sqrt{p}\sqrt[3]{q})$ and how to find the minimal polynomial of $\sqrt{p}\sqrt[3]{q}$ over $\mathbb{Q}$ ? Mechanism of Screenshot Basically I with my team are figuring out a way to block screenshots taken on our corporation's computers (Mac mostly). I have searched it extensively and found that there is something called Screen buffer which is being accessed by any screenshot taking software (eg. Snipping Tool etc). I tried to find the exact mechanism and the actual implementation of such softwares but with no luck. Also I found out that Netflix uses some kind of technology which corrupts screenshot image and blackens it. I did not find any actual mechanism or implementation to study it further. I also came across something called Hardware overlays but did not understand it properly in order to use it for actual implementation. I have considered a way to edit scancode maps in registry but I am looking for a more general way. I read a few articles for apple's FPS though. Can somebody please guide me through this? Some good resources for the same would be highly appreciated. Any particular or relevant forums or subs to discuss this are also welcome Arrows describing matrix Lets say I have a 5x5 matrix. I want to place 2 leftrightarrows (with descriptions "3", "2") underneath the matrix, but really close to it: first pointing from col1 to col3 and second from col4 to col5. Plus updownarrows with similar outcome. How can I achieve that?  draft:  1 1 1 | 1 1  &lt;--> &lt;-> I am currently working my way through "A Concise Introduction to Pure Mathematics" by Martin Liebeck, and have been stuck on an excersise for a couple of days now. The question reads:  "Show that for an integer n $\geq2$, the period of the decimal expression for the rational number $\frac{1}{n}$ is at most $n-1$."  I've been trying to solve this without making any substantial progress. And yes, I have seen explanations that when performing a long division the decimal expression either terminates to $0$ or eventually repeats. But I haven't seen any proof of this that I've been satisfied with, even less do I know how to formalise this type of proof. I've tried to write out long division with arbitrary digits, but that obviously turns out to be too much of a hassle and basically impossible to draw any conclusions from. I saw a video of Johann Cruyff , isn't that against the rules? How to make a complaint about grades? My professor announced the grades. He told us in each part what grades we had. My oral presentation for the project was way better than other students. But he just gave me 89 for oral and gave others 88.  I think it is not fair at all, because most of the students were not clear or the did not consider timing. He also told me that "your presentation was very good".  Also, I performed very well on the final exam but he also did not give me the 100. I think it is not fair.  How can I make a complaint? What should I write? I have a PostgreSQL table. select * is very slow whereas select id is nice and quick. I think it may be that the size of the row is very large and it's taking a while to transport, or it may be some other factor. I need all of the fields (or nearly all of them), so selecting just a subset isn't a quick fix. Selecting the fields that I want is still slow. Here's my table schema minus the names: integer                  | not null default nextval('core_page_id_seq'::regclass) character varying(255)   | not null character varying(64)    | not null text                     | default '{}'::text character varying(255)   |  integer                  | not null default 0 text                     | default '{}'::text text                     |  timestamp with time zone |  integer                  |  timestamp with time zone |  integer                  |   The size of the text field may be any size. But still, no more than a few kilobytes in the worst case. Questions  Is there anything about this that screams 'crazy inefficient'? Is there a way to measure page size at the Postgres command-line to help me debug this? How can you encode a string to Base64 in JavaScript? I have a PHP script that can encode a PNG image to a Base64 string.  I'd like to do the same thing using JavaScript. I know how to open files, but I'm not sure how to do the encoding. I'm not used to working with binary data. Evaluating $\prod_{n=1}^{\infty}\left(1+\frac{1}{2^n}\right)$ Restore deleted photos I accidentally deleted the entire "downloaded" album full of pictures from my Samsung Galaxy S2 (SPH-D710) and am trying to use a  I downloaded.  My phone will not show up as a remove-able storage device on my computer, or on the program. I have tried to change the USB settings on my phone but there is no USB settings when I go to Settings > Wireless and networks as most information instructs.   I found the setting for USB debugging by going to Settings > Developer options and can turn that on and off, but that is the only setting I can find relating to USB storage.   When I connect it to the USB cord it gives me MTP or PTP options but again no USB options.   Any advice??? Thank you! Since I installed EasyTag on my Arch Linux several other programs use EasyTag instead of Nautilus as filebrowser.  For example, Firefox starts EasyTag if I click on "open containing folder".  Where can I set Nautilus as my "standard file browser"? The below-mentioned question is asked in my exam, I think my answer is correct, please tell if I am right, I have to challenge the question in 2 days if its answer given is wrong.  correct answer is given by examiner. candidate answer is the answer I ticked as correct.  In the following question, a sentence has been given in Direct/Indirect speech. Out of the four alternatives suggested, select the one which best expresses the same sentence in Indirect/Direct speech.     They said, “We pray everyday.”   Options:   1) They said that they have been praying every day.   2) They said that they pray every day.   3) They said that they prayed every day.   4) They said that we prayed every day.   Correct Answer: They said that they prayed every day.   Candidate Answer: They said that they pray every day.      as praying is a habitual action ,confirmed by everyday , so prayed is incorrect , i think. Why do some bad traits evolve, and good ones don't? Force MacBook to drain the battery while connected to charger I leave my MacBook Pro on my desk nearly all the time, connected to the charger with the lid closed, connected to an external display.  I've heard this is bad for the battery health, and everyone in my office have to replace swollen batteries every couple of years. I want to regularly discharge the battery, per , but I don't want to physically unplug it because that temporarily turns off the external monitor, and then I have to reconnect the monitor.  So I am looking for a software method of disabling the power input, to force the laptop to discharge its battery to 20% and then re-enable the power input. So I have these two wheels parented to the leg of a robot. I wanna make them spin a few times but they're spinning around the wrong axis. With other objects I could just press R, Y, Y to make them spin right when they're already at an angle, but for some reason it doesn't work with these. Would be amazing if someone helped me fixing this! Given $y_n=(1+\frac{1}{n})^{n+1}$ show that $\lbrace y_n \rbrace$ is a decreasing sequence Given  $$ y_n=\left(1+\frac{1}{n}\right)^{n+1}\hspace{-6mm},\qquad n \in \mathbb{N}, \quad n \geq 1. $$ Show that $\lbrace y_n \rbrace$ is a decreasing sequence. Anyone can help ?  I consider the ratio $\frac{y_{n+1}}{y_n}$ but I got stuck.