Use of “where” in a question when referring to something other than a place
“situation where” vs. “situation in which”
There seems to be a preference for to have the    18 mm - 55 mm 55 mm - 250 mm   lenses, but no mention of why they're better than a single 18-200mm. Could someone please explain why the two separate are better than the one combined, and if anyone has quantified this difference?  (I'm curious about Canon in particular.) Hi I make this class A amplifier but how to replace R5 (10 ohm/10 W) with transistor because its getting really hot and how to achieve up to 10 Watt with +/- supply. I have +/-25v with 4A please help Convert a character digit to the corresponding integer in C Living potato clock? Why does reversing serial upvoting not reverse the Mortarboard badge? user has serial up-voting reversed, but he still have badge Mortarboard.   Is it correct behavior of badges? I suppose it should be reversed too.  And will this 200 daily reputation (2012-03-20) score for the Epic, and Legendary badges? I've noticed that the majority of Ubuntu help websites present apt commands in the following format:  sudo add-apt-repository ppa:[ppa-address] sudo apt-get update sudo apt-get install [application-name]   But I know that apt commands like this one work too:  sudo add-apt-repository ppa:[ppa-address] &amp;&amp; sudo apt-get update &amp;&amp; sudo apt-get install [application-name]   Is there a particular reason that most sites present in the first format? Are there known issues with chaining commands with &amp;&amp;, or to put it another way are there any benefits/drawbacks to using either method?  Further, other then loss of internet, are there any circumstances in which an apt command might fail? Centos7 can't boot with shim-x64-15-7.el7_9.x86_64 The floowing is serial console output: BdsDxe: starting Boot0003 &quot;CentOS Linux&quot; from HD(1,GPT,A51EC18C-6831-4D47-B93E-B20DBC3F30BF,0x800,0x64000)/\EFI\centos\shimx64.efi  UEFI: Attempting to start image. Description: CentOS Linux FilePath: HD(1,GPT,A51EC18C-6831-4D47-B93E-B20DBC3F30BF,0x800,0x64000)/\EFI\centos\shimx64.efi OptionNumber: 3.  !!!! X64 Exception Type - 0D(#GP - General Protection)  CPU Apic ID - 00000000 !!!! ExceptionData - 0000000000000000 RIP  - 00000000BF2E5D5C, CS  - 0000000000000038, RFLAGS - 0000000000010006 RAX  - 00000000BFF5FE50, RCX - 000000000000001F, RDX - 00000000BFF31F28 RBX  - 00000000BF352FB0, RSP - 00000000BFF31E50, RBP - 00000000000023C0 RSI  - 00000000BFF31F28, RDI - 0000000000000068 R8   - 00000000BDB8C018, R9  - 000000000000211E, R10 - 00000000BDC6C010 R11  - 00000000BFF31E9A, R12 - 00000000BE791068, R13 - 00000000BF339018 R14  - 00000000BEE21018, R15 - 0000000000000068 DS   - 0000000000000030, ES  - 0000000000000030, FS  - 0000000000000030 GS   - 0000000000000030, SS  - 0000000000000030 CR0  - 0000000080010033, CR2 - 0000000000000000, CR3 - 00000000BF401000 CR4  - 0000000000000668, CR8 - 0000000000000000 DR0  - 0000000000000000, DR1 - 0000000000000000, DR2 - 0000000000000000 DR3  - 0000000000000000, DR6 - 00000000FFFF0FF0, DR7 - 0000000000000400 GDTR - 00000000BF3EEA98 0000000000000047, LDTR - 0000000000000000 IDTR - 00000000BEE1F018 0000000000000FFF,   TR - 0000000000000000 FXSAVE_STATE - 00000000BFF31AB0 !!!! Find image based on IP(0xBF2E5D5C) /build/work/af60adde42b1d1ad5be2a01e4924bb905248/google3/blaze-out/k8-opt/genfiles/third_party/edk2/ovmf_x64_csm_debug_workspace_dir/ovmf_x64_csm_debug_edk2_files_dir/Build/OvmfX64/DEBUG_CLANG38/X64/OvmfPkg/8254TimerDxe/8254Timer/DEBUG/Timer.dll (ImageBase=00000000BF2E4000, EntryPoint=00000000BF2E5AB5) !!!! Large text files load not working on android What's needed for a complete backup system? For my new server, I want to setup a proper backup solution. I've found a great setup that will do twice-daily incremental backups via Dropbox. I plan on backing up my various databases, the webroot directory, the /etc directory/repository, and /var/log.   What else do I need to know to do a proper backup, and what is the standard setup here to ensure you can quickly restore from a backup in the case of a system failure?  I'm thinking of using Puppet, as it describes how the system should be. My restore procedure would look like this:   Install Puppet Run my puppet config Restore my backups from Dropbox (Should I create a script to do this? Probably)   This should also let me create a clone of my production server for use in dev environments, correct? Am I missing anything of importance? How are the AES S-Boxes calculated? I'm trying to understand how the AES S-Boxes are calculated. I understand how the multiplicative inverse is calculated over $GF(2^8)$, but I'm confused by the description of the affine transformation. I haven't been able to Google a good explanation of how the S-Box values are calculated. Can someone explain how this works, starting after the calculation of the multiplicative inverse? Why might right aligned field labels be better? For the longest time, I've used left-aligned labels in my forms, like this:    I did this because I thought having the labels left aligned made it easier for readers to scan the list of labels.  However, I found my axiom challenged recently while watching  from , in which Billy asserts that right-aligned labels are simply better, like this:    I've done a bunch of research and found a lot of discussion, including , which compares and contrasts the approaches, but nothing definitive.  In particular, I haven't been able to find anything to indicate why Billy Hollis changed his opinion from left- to right- alignment for labels (apparently he switched around 2007).   I figure Billy's too smart to have made the change without evidence - so I'm interested in seeing that evidence for myself. How to show that $\sum_{k=1}^n k(n+1-k)=\binom{n+2}3$? I've just updated to macOS 10.12 and when I try to execute srm in Terminal, it says -bash: srm: command not found.   Is srm removed? How to fix this? Transferring Fallout 4 Saves (PS4) How do I run an executable file with a double click? I'm trying to run an executable (testdisk) but double click doesn't work. The only way is to run:  sudo ./testdisk   from terminal. But I'd like to open executables with double click in future. How can I do this? After a botched upgrade from Ubuntu 14.04 to Ubuntu 16.04 I had to wipe my system and start all over. This time I decided to go with a much less CPU intensive desktop environment and installed Lubuntu 16.04-1.  My problem: when I run Steam from the menu shortcut it acts like it is doing nothing. However it does show up in the task manager. If I just type steam in the terminal I get the following.  michael@michael-HP-Pavilion-dm1-Notebook-PC:~$ steam Running Steam on ubuntu 16.04 64-bit STEAM_RUNTIME is enabled automatically grep: symbol lookup error: grep: undefined symbol: pcre_jit_stack_alloc grep: symbol lookup error: grep: undefined symbol: pcre_jit_stack_alloc /bin/bash: /home/michael/.local/share/Steam/ubuntu12_32/steam-runtime/amd64/lib/x86_64-linux-gnu/libtinfo.so.5: no version information available (required by /bin/bash) grep: symbol lookup error: grep: undefined symbol: pcre_jit_stack_alloc awk: /home/michael/.local/share/Steam/ubuntu12_32/steam-runtime/amd64/lib/x86_64-linux-gnu/libtinfo.so.5: no version information available (required by /lib/x86_64-linux-gnu/libreadline.so.6) Installing breakpad exception handler for appid(steam)/version(1468023329) libGL error: unable to load driver: r600_dri.so libGL error: driver pointer missing libGL error: failed to load driver: r600 libGL error: unable to load driver: swrast_dri.so libGL error: failed to load driver: swrast   Then nothing happens including steam doesn't show up in the task manager. Now I did find the command.  LD_PRELOAD='/usr/$LIB/libstdc++.so.6' DISPLAY=:0 steam   This does run Steam but it is not a real solution in my eyes. How can I fix it? If I know for two numbers a and b that    $${a &lt; b }$$  Then is it correct to say that    $$ a \leq b $$  I know that the second statement is true as long as the first one is. It seems OK as it is true but from the other side it seems kinda weird (to me), to say that, if you know, that a is strictly less that b.It's like you lose some extra information. Prove the inequality and limitation Suppose $\{a_k\}$ ,$\{b_k\}$ and $\{\xi_k\}$ are non negative, and for all $k\ge 0$ , we have $$a_{k+1}^2\le(a_k+b_k)^2-\xi_k^2$$   Prove   1.$$\sum_{i=1}^{k}\xi_i^2\le(a_1+\sum_{i=0}^kb_i)^2$$   2. If $\{b_k\}$ also satisfy $\sum_{k=0}^{\infty}b_k^2\lt+\infty $, then $$\lim_{k\to\infty}\frac{1}{k}\sum_{i=1}^k\xi_i^2=0$$   After doing this transformation:$$\xi_k^2\le(a_k+b_k)^2-a_{k+1}^2$$ $\Rightarrow$ $$\sum_{i=1}^{k}\xi_k^2\le(a_1+b_1-a_2)(a_1+b_1+a_2)+(a_2+b_2-a_3)(a_2+b_2+a_3)+\cdots(a_k+b_k-a_{k+1})(a_k+b_k+a_{k+1})$$ then I can't move forward any more. Word style "keep with next" except on last item Prove that the additive group $ℚ$ is not isomorphic with the multiplicative group $ℚ^*$. Prove that $ℚ^*_{&gt;0}$ is not isomorphic with $ℚ$.