when running Software Updater from my Ubuntu 14.04 Desktop install, I get the following errors:  W:Failed to fetch http://archive.ubuntu.com/ubuntu/dists/$(lsb_release/-sc)/binary-i386/Packages  404  Not Found [IP: 91.189.88.153 80],  W:Failed to fetch http://archive.ubuntu.com/ubuntu/dists/$(lsb_release/universe/binary-i386/Packages  404  Not Found [IP: 91.189.88.153 80], W:Failed to fetch http://it.archive.ubuntu.com/ubuntu/dists/trusty-updates/main/binary-i386/Packages  Hash Sum mismatch,  W:Failed to fetch http://it.archive.ubuntu.com/ubuntu/dists/trusty-updates/universe/binary-i386/Packages  Hash Sum mismatch   How may I fix this? Thank you. Regards
There are now errors when updating and I cannot install most software due to a corrupted  /etc/apt/sources.list   file. Is there a copy I can download to replace it?  The file would be for Ubuntu 12.04 (Final Beta) in the United States.
SSH Permission denied (publickey) I am trying to connect to a Linode (running Ubuntu 12.04 LTS) from my local machine (also running Ubuntu 12.04 LTS)  I have created a private and public key on my local machine and copied my public key to my Linode's authorized_keys file.  However, whenever I try to ssh to my Linode I get the error message Permission denied (publickey).    It's not a problem with how ssh is set up on my Linode because I can ssh to it from my Windows machine using key authentication.    In my .ssh directory on my local Ubuntu machine, I have my id_rsa and id_rsa.pub files.  Do I need to create an authorized_keys file on my local machine?    EDIT:  This is what I get when I run ssh -vvv -i id_rsa [youruser]@[yourLinode]:  debug3: authmethod_lookup publickey debug3: remaining preferred: keyboard-interactive,password debug3: authmethod_is_enabled publickey debug1: Next authentication method: publickey debug1: Offering RSA public key: id_rsa debug3: send_pubkey_test debug2: we sent a publickey packet, wait for reply debug1: Authentications that can continue: publickey debug2: we did not send a packet, disable method debug1: No more authentication methods to try. Permission denied (publickey). Is the electromagnetic spectrum discrete? I'm just starting to learn physics and I have a question (that is probably stupid.)  I learned that energy levels that the bound electron can have are discrete. I also learned that when an electron transitions from one level to another, a photon with a specific wavelength (energy) is created and released into the wild.  My question is this: are there holes in the electromagnetic spectrum, values of frequency that the created photon can't possibly have? How can I develop my Android game for different phone resolutions? Does the limit $\lim _{x\to 0} \frac 1x \int_0^x \left|\cos \frac 1t \right| dt$ exists ? If it does then what is the value ?   I don't think even L'Hospital's rule can be applied . Please help . Thanks in advance Why screen resolution remains 640x480 when I close a game? Photons travel at the fastest speed in our universe, the speed of light.  Do photons have acceleration? Between you and ("me" or "I")? Is it correct to say "between you and me" or "between you and I"?  I am not a native English speaker, so please bear with me. What's the simplest way to add a click event handler to a canvas element that will return the x and y coordinates of the click (relative to the canvas element)?  No legacy browser compatibility required, Safari, Opera and Firefox will do. Can I put a rack on a carbon road bike? I got a carbon-framed  recently but I also want to use it for commuting to and from work and I want a place to put my lock and other stuff on the bike. Is it possible to have a rack on this kinda bike. Multiple one to many relationships in series I am making a DB for storing reports that have following fields:  Ad_system, Ad_Campaing, Ad_Group, Keyword, Date, Impressions, Clicks, Conversions   Logic is that, Ad_system can have multiple Ad_Campaings, Ad_Campaing can have multiple Ad_Groups and Ad_Groups can have multiple Keywords, and for every Keyword there is a report. Should It be like this? Because it kind of makes sense to me, but it doesn't look correct. Primary key can also be:  ad.system.name for first table  ad.system.name ad.campaing.name for second table  ad.system.name ad.campaing.name ad.group.name for third table  ad.system.name ad.campaing.name ad.group.name keyword for fourth table  They will always be unique, but then Report will always have all DB columns in it, so it's kind of redundant.  Is the approach that I have in the diagram below correct? Or is a better one what I just described? If I am not mistaken both should satisfy 3rd NF. Opening website external links in new window -- published usability tests Which livestock is the most efficient food source? Suppose $X_n$ is the fortune of a gambler after $n$ th game. Then the game is called fair (Breiman 1968) if   $$E[X_{n+1} \mid X_1, \dots, X_n] = X_n \forall n$$  My question is why a fair game is not defined as the following   $$E[X_{n+1}] = E[X_n] \forall n$$ i.e. $$E[X_{n+1}- X_n]=0$$. This should be the proper definition as a fair game is where avg. gain is zero. Nothing conditioning should be there. Can someone pgfplots the following picture concerning confidence intervals? I've been trying to use the following code to produce it, but have no idea how to shade in the tails I am interested in. By the way, the line pointing the (100-C/2)% can be an arrow, does not have to be squiggly as depicted in the picture.   \begin{tikzpicture}[ every pin edge/.style={&lt;-}, every pin/.style={fill=yellow!50,rectangle,rounded corners=3pt,font=\small}] \begin{axis}[every axis plot post/.append style={   mark=none,domain=-3:3,samples=50,smooth}, clip=false, axis y line=none, axis x line*=bottom, ymin=0, xtick=\empty, ] \addplot {\gauss{0}{0.5}}; \addplot {\gauss{0}{1}}; \node[pin=70:{$\hat{\theta}_1$}] at (axis cs:0.57,0.5) {}; \node[pin=270:{$E(\hat{\theta} = 0$}] at (axis cs:0,0) {}; \draw[dashed] (axis description cs:0.5,0) -- (axis description cs:0.5,0.92); \end{axis} \end{tikzpicture} Copy & Pasting from Photoshop to Illustrator loses transparency I often run into this issue. I'm creating a file in Photoshop with masked layers etc. I want to make the final output available for some mock-ups in Illustrator, so I rasterize the layers and marquee select the entire area, copy and move to Illustrator.  Pasting the area in Illustrator flattens all transparencies, which is quite annoying. I'm left with my object and a flat white background.  Is there a reason for this? How to analyze trend in non-periodic time series Suppose I have following non-periodic time series. Obviously the trend is decreasing and I would like to prove it by some test (with p-value). I am unable to use classic linear regression due to strong temporal (serial) auto-correlation among values.  library(forecast) my.ts &lt;- ts(c(10,11,11.5,10,10.1,9,11,10,8,9,9,                6,5,5,4,3,3,2,1,2,4,4,2,1,1,0.5,1),             start = 1, end = 27,frequency = 1) plot(my.ts, col = "black", type = "p",      pch = 20, cex = 1.2, ylim = c(0,13)) # line of moving averages  lines(ma(my.ts,3),col="red", lty = 2, lwd = 2)     What are my options? I left them (at) home Consider this question:  Where are they (things or people)?  Would the following answer be with (at), without it or either one?  I left them (at) home  I have done a quick Google search and found quotes for both cases, with and without:  This Widow's 4 Kids Were Taken After She Left Them Home Alone. Leaving Your Child Home Alone - KidsHealth Gerry said, &quot;I left them at home.&quot; Gerry sat down and turned on the TV set just as Mark would have done.  I read about &quot;home&quot; being an adverb but also know &quot;stay at home moms&quot; for example. So you see I need definite answers. The equivalence of sample correlation and R statistic for simple linear regression How to get part name in LaTeX ? Firefox - Websites with custom fonts not displaying