I am in a location where I can only use my mobile wifi tethering &amp; hotspot. I downloaded and installed linux 20.04 server but unfortunately those titled commands are not included. And to get them i have to have internet using the apt and that is not possible for me now. 1- I am not sure why such commands are not included in the ISO files. 2- in such case I need your help a- How to download,install and configure drivers for a USB wifi adapter. b- How to configure the USB wifi network. c- How to download and install and configure the installation commands. only I can reach the internet through tethering between my mobile and my laptop.
I have a friend who has got a computer that is not connected to the Internet. Is there any way to install software offline easily?
For a prime $p \equiv 1$ or $3$  (mod $8$), show that the equation $x^{2} + 2y^{2} = p$ has a solution.   I'd like to see an elementary proof. Comments are useful. Many, many posts need some small amount of meta discussion, and comments fulfill this need.   Comments are also noisy and distracting. Occasionally, someone will post an insightful and informative comment that complements the post its attached to... But more often, they're tangential, quickly irrelevant and in the way: stale comments show up first, making newer comments less visible.  The guidance here for a long time has been that comments are transient, . And yet, some do hang around for months or years because .   So let's fix that.   I propose that all comments older than 7 days be hidden by default unless the comment has been up-voted in the past 30 days. Hidden comments should be indicated by a note below the post ("add / show 3 more comments") and made visible to anyone who cares to click it.   This doesn't destroy anything, but it would get it out of the way of most readers - and hopefully encourage folks to edit it into the actual answers as a result.  Note: I previously suggested this . Other  have been . However, I'm not suggesting that comments be automatically deleted, and they should be hidden based purely on the age / activity of the comment itself, not of the post to which they're attached. Zero visibility while editing a message in a chat room Say if I define a power series over some arbitrary field $F$ as   $$a = \sum^{ \infty }_{i = 0} a_{i} X^{i} $$  Then can I say:  $$ab = \sum^{ \infty }_{i = 0} \sum^{ \infty }_{j = 0} a_{i} b_{j} X^{i + j} $$ Bootstrap Paradox in Interstellar Keeping tables/figures close to where they are mentioned Is there any package or a method to force LaTeX to keep floating environments like table and figure closer to where they are declared? Most textbooks introduce differentiable manifolds via . This has the advantage of being concrete, but the disadvantage that the local coordinates are usually completely irrelevant- the choice of atlas and chart is arbitrary, and rarely if ever seems to play any role in differential geometry/topology.  There is a much better definition of differentiable manifolds, which I don't know a good textbook reference for, via . This definition does not involve any strange arbitrary choices, and is coordinate free. Paragraph 3 in Wikipedia (which is the actual definition) states:   A differentiable manifold (of class $C_k$) consists of a pair $(M, \mathcal{O}_M)$ where $M$ is a topological space, and $\mathcal{O}_M$ is a sheaf of local $R$-algebras defined on $M$, such that the locally ringed space $(M,\mathcal{O}_M)$ is locally isomorphic to $(\mathbb{R}^n, \mathcal{O})$.   This confuses me, because I don't see why such a sheaf should be acyclic, or where conditions like "paracompact" or "complete metric space" or "second countable Hausdorff" are implicit. So either:   The wikipedia entry has a mistake (I would want to sanity-check this before editing the entry, because this is such a fundamental definition which thousands must have read). Somewhere in that definition, the condition that $M$ be paracompact is implicit.   Question: Should the definition above indeed require that $M$ be second-countable Hausdorff or paracompact or whatever? Or is it somehow implicit somewhere, and if so, where?    Also, is this definition given carefully in any textbook?  Update: I have editted the Wikipedia article to require that $M$ be second-countable Hausdorff. But I'm still wondering if there is a textbook covering this stuff, and whether requiring the sheaf to be acyclic might have worked instead as an alternative. When creating accounts on Windows 10, you get a choice between "Your family" and "Other users".  If you choose "Your family" you are forced to use a Microsoft account to sign in. There are various reasons why one wouldn't want to do that, such as too much sharing of private information with Microsoft, etc.  If you choose "Other users" you can create regular accounts just fine. However, if you need to setup time limits for some accounts, it is impossible to do so. It is a feature exclusive to "Your family". Not all time-restricted users I want to create are my family, and not everyone is okay with sharing their info with Microsoft.  So, is there a way to setup login time limits for the "Other users" type of accounts? Calculating the limit $\lim((n!)^{1/n})$ Find $\lim_{n\to\infty} ((n!)^{1/n})$. The question seemed rather simple at first, and then I realized I was not sure how to properly deal with this at all. My attempt: take the logarithm,  $$\lim_{n\to\infty} \ln((n!)^{1/n}) =  \lim_{n\to\infty} (1/n)\ln(n!) =  \lim_{n\to\infty} (\ln(n!)/n)$$ Applying L'hopital's rule:  $$\lim_{n\to\infty} [n! (-\gamma + \sum(1/k))]/n! = \lim_{n\to\infty} (-\gamma + \sum(1/k))=  \lim_{n\to\infty} (-(\lim(\sum(1/k) - \ln(n)) + \sum(1/k))  = \lim_{n\to\infty} (\ln(n) + \sum(1/k)-\sum(1/k)  = \lim_{n\to\infty} (\ln(n))$$ I proceeded to expand the $\ln(n)$ out into Maclaurin form $$\lim_{n\to\infty} (n + (n^2/2)+...) = \infty$$ Since I $\ln$'ed in the beginning, I proceeded to e the infinity  $$= e^\infty  = \infty$$  So am I write in how I approached this or am I just not on the right track? I know it diverges, I was just wanted to try my best to explicitly show it. What are the alternatives for storing client side encrypted data? I want to store client side encrypted data in Drupal 7, so that it is encrypted on the client end, and stored and transmitted in encrypted form. The password is never transmitted or stored on the server. The only modules I have found which do this are  and  but they are for Drupal 6. I need something that is user specific, so that different users can use different keys, rather than a single key or a set of keys used on the server end. Are there any similar modules for Drupal 7? Clipping a GEE Image with Python API I am looking for a way to clip image collection by a given polygon geometry with Python API, The GEE JavaScript equivalent is simply ImageCollection.clip(geom) () With the python API I get the error: 'ImageCollection' object has no attribute 'clip'.  I'm adding my code after using .mean() as a reducer My code: set the boundary polygon my_boundary = ee.Geometry.Polygon([ [[-5, 40],[65, 40],[65, 60],[-5, 60],[-5, 60]]] ,proj=None) #set the ImageCollection and Image img_Collection = ee.ImageCollection('COPERNICUS/S5P/NRTI/L3_NO2').filterDate('2020-03-01', '2020-03-27').select('NO2_column_number_density') my_Image=img_Collection.mean().clip(my_boundary) #Create Ipyleaflet map my_map = ipyleaflet.Map(zoom=7) my_map.add_layer(layer=my_Image) my_map error: AttributeError: 'Image' object has no attribute 'model_id' We've heard it many times, nothing can escape the gravity of a black hole, even light once it's past the event horizon.  If this is true, how can a black hole emit anything?  are massive black holes that have consumed enormous amounts of matter and energy, and then blasted it back out into the universe.  How is this possible?  Time stands still in a black hole, that in itself should stop anything from moving. How do you change the size of figures drawn with Matplotlib? How do you change the size of figure drawn with Matplotlib? Fibonacci divisibilty properties $ F_n\mid F_{kn},\,$ $\, \gcd(F_n,F_m) = F_{\gcd(n,m)}$ Can any one give a generalization of the following properties in a single proof? I have checked the results, which I have given below by trial and error method. I am looking for a general proof, which will cover the all my results below:   Every third Fibonacci number is even. 3 divides every 4th Fibonacci number. 5 divides every 5th Fibonacci number. 4 divides every 6th Fibonacci number. 13 divides every 7th Fibonacci number. 7 divides every 8th Fibonacci number. 17 divides every 9th Fibonacci number. 11 divides every 10th Fibonacci number. 6, 9, 12 and 16 divides every 12th Fibonacci number. 29 divides every 14th Fibonacci number. 10 and 61 divides every 15th Fibonacci number. 15 divides every 20th Fibonacci number. Why I cannot ping 192.168.0.108 (my computer IP?) How many Marvel Earths (Universes) are there? I know that there are at least 3 Marvel Universes:  Marvel Cinematic Universe -    Has all of the main ongoing Marvel movies    (1, 2)  (1, 2, 3)  (1, Age of Ultron) etc    Marvel's Ultimate Universe -    Has the other Marvel movies    (1, 2, 3, Origins: Wolverine, First Class, The Wolverine, Days of Future Past)  (1, 2)  etc       Main comic book continuity This is the big one, it contains         etc     Then there are apparently off-shoot Earths, continuities which deviate from the main continuity (Earth 616). How many Marvel Earths (Universes) are there?   Further Reading: Difference between alphabet $a$ and "a" I have a very simple problem. I want to write "a" in an equation, however output is .... Please see output. How i can overcome this problem? My application listens on port 8180.  When I am trying to connect to port 8180 locally. Connection got refused. But when I am trying to connect to port with ip . I am able to connect.  [root@MUMLGOMAPP002 ~]# telnet 10.209.129.54 8180 Trying 10.209.129.54... Connected to MUMLGOMAPP002 (10.209.129.54). Escape character is '^]'. ^] telnet&gt; q Connection closed.   [root@MUMLGOMAPP002 ~]# telnet localhost 8180 Trying 127.0.0.1... telnet: connect to address 127.0.0.1: Connection refused telnet: Unable to connect to remote host: Connection refused   My interface is :  [root@MUMLGOMAPP002 ~]# ifconfig bond0     Link encap:Ethernet  HWaddr 44:1E:A1:73:F7:50           inet addr:10.209.129.54  Bcast:10.209.129.63  Mask:255.255.255.224           UP BROADCAST RUNNING MASTER MULTICAST  MTU:1500  Metric:1           RX packets:322997568 errors:23 dropped:0 overruns:0 frame:0           TX packets:304470664 errors:0 dropped:0 overruns:0 carrier:0           collisions:0 txqueuelen:0           RX bytes:213628580915 (198.9 GiB)  TX bytes:217449664400 (202.5 GiB)   I would like to know what is the difference between telnetting localhost and ip. ContentVersion Content-Type I need to stream a file from Salesforce in our webapplication. To make sure the file is properly opened, I have to set Content-Type header.  How to retrieve the Content-Type (MIME) of a file?  I expect values like: image/png, application/pdf, text/html etc.  How to get these values? I am using the Java and a SOAP client to retrieve the data. I am using PHP with Apache on Linux, with Sendmail. I use the PHP  function. The email is sent, but the envelope has the Apache_user@localhostname in MAIL FROM (example nobody@conniptin.internal) and some remote mail servers reject this because the domain doesn't exist (obviously). Using mail, can I force it to change the envelope MAIL FROM?  EDIT: If I add a header in the fourth field of the mail() function, that changes the From field in the headers of the body of the message, and DOES NOT change the envelope MAIL FROM.  I can force it by spawning sendmail with sendmail -t -odb -oi -frealname@realhost and piping the email contents to it. Is this a better approach?  Is there a better, simpler, more PHP appropriate way of doing this?  EDIT: The bottom line is I should have RTM. Thanks for the answers folks, the fifth parameter works and all is well.