view friends email with fb api, or send them a email with invite
Does Facebook allow a user to give my app access to their friends email addresses?
How can I find infinity focus on a kit lens with no markers? I have a kit lens which has no markers. What would be a recommended way to find infinity focus on this lens?  I plan to shoot objects at night -- not necessarily stars or the moon. So, adjusting the focus using the viewfinder may not be an option. How do you check for whether a device is in a wifi deadzone? I have a rather long footnote which breaks a listing in two parts, unnecessarily.  Since the listing is more important then the footnote I'd rather lake to have the footnote split.   Can I customize (one or all) footnotes to have a maximal length before they are continued on the next page? Or can I manually split a footnote in two to get the effect? How do I combine the NBT tags from two separate commands? I have two commands I'd like to combine into one, but I'm not sure how to go about combining them. Is this possible?   Here are the commands. They work individually, I just can't seem to get them to work together:  /give @p jukebox 1 0 {CanPlaceOn:["minecraft:melon_block"]}     /give @p jukebox 1 0 {display:{Name:"Box"}}   Can you help me to add one of the commands to the other one? Prove if $f:[a,b] \rightarrow \mathbb{R}$ is integrable, then so is $|f|$ and $\left|\int_{a}^{b}f(x)dx\right| \leq \int_{a}^{b}|f(x)|dx$ Prove that if $f:[a,b] \rightarrow \mathbb{R}$ is integrable, then so is $|f|$ and $\left|\int_{a}^{b}f(x)dx\right| \leq \int_{a}^{b}|f(x)|dx$   I already proved that |f| is integrable, but how do I show that $|\int_{a}^{b}f(x)dx| \leq \int_{a}^{b}|f(x)|dx$   ? How can I reset my menus? Why aren't my guide and other dead NPCs respawning in Terraria? I am currently in hard mode and during a blood moon, several of my NPCs including my guide and my healer died. it's been several in game "days" now and they have yet to respawn. Is there a way to check why they aren't respawning?   Is there a list of reasons for the NPCs to not respawn?   Edit in reponse to lunbok's answer:  1. They don't have appropriate housing - There is an in-game housing query function (changes your cursor into a ?) that lets you click on your house to see if it is still a suitable house and I clicked in every room in my house and they are all listed as "This housing is suitable" or "This housing is already occupied".  2. Their spawn conditions aren't met anymore. - This doesn't explain why my guide isn't respawning since they don't need a condition to respawn (other than having a suitable housing which the point above already prove isn't the problem).  3. There's a goblin invasion going on. - Do the invasions last that long? It has been about two reals days and a lot more in-game "days" now. As far as I can tell there shouldn't be an invasion going on.  4. It could be because you built your house in a part of the world that is now corrupted What's the difference between centre of mass & centre of gravity for massive bodies? My book says:     For most of the small objects, both are same. But for mammoth ones, they are really different ones. And in a gravity-less environment, COG is absent; COM still exists.   Ok, what's the big deal when things are small and big? How these two :  &amp; ? How does an Intelligence penalty affect skill points when character-building/leveling-up? Run as a different user on a shortcut How do I run as a different user on a shortcut in Windows 7?   On Windows XP, I had the ability to mark a shortcut as being run by a different user, so that every time I ran it it would prompt me for a username/password. This let me have two shortcuts for things like , one for my normal account and one for my domain administrator account which has access to production servers.  I can get to the 'Run as different user' option with Shift + right-click, but I can't see an option anywhere that would let me mark the shortcut as doing this every time. Firefox 37.0.2 not opening (removing firefox did not help) runing ubuntu 14.04 LTS For every $p\in [1,\infty)$, consider the set $\ell^p$ of real sequences $x=(x_n)=(x_1,x_2,\ldots)$ such that $\sum_{n=1}^\infty |x_n|^p&lt;\infty$. This is a Banach space with the norm $\Vert x\Vert_p=(\sum|x_n|^p)^{1/p}$.  I have the following problem:     Is it true that $\ell^p=\bigcup_{1\leq q&lt;p}\ell^q$ for $p&gt;1$?   I don't think it is true, but I'm having problems to show this. Clearly, the statement is true for some $p&gt;1$ iff it is true for every $p&gt;1$.  I'm trying to find a sequence $(a_n)$ such that $\sum |a_n|^s$ converges iff $s\geq 1$. I've tried many sequences (such as $(n^{1+1/n})$, involving $\log$, etc...), but none of them worked. I have Raster data for a country which has Evaporation Data in its pixels. I also have Vector layer which has the 30 cities of the country.   What I need is the average Evaporation value of each city from the raster data using ArcGIS?  I have access to the spatial analyst extension. The differences between TeX engines I am confused about what TeX and its offspring (LaTeX, pdfTeX/pdfLaTeX, e-TeX, ConTeXt, LuaTeX, etc.) are.  Some, like LaTeX, seem like add ons to TeX (maybe a change to the eyes and mouth, but not stomach). Others, like pdfTeX, seem like changes to the underlying system (i.e., a change to the stomach).  Is there a good reference that explains the differences and the evolution? How to reduce the size of VMware disk My Ubuntu image VMware disk has grown to 5GB physical file size. It's a dynamically growing disk with the maximum capacity of 8GB. I cleaned some stuff inside Linux distro and now inside it occupies 3GB. Obviously the physical file size didn't shrink back automatically. Is there a way (if possible free of charge) to shrink this disk back to ~3GB?  I need this to fit the image on the DVD. Finding square root without using sqrt function? Duality discrete math problem This is the only answer I got wrong on my HW and the prof does not want to give us the correct answers before our midterm     The dual of a compound proposition that contains only the logical operators $\lor$ , $\land$ , and   $\neg$ is the compound proposition obtained by replacing each $\lor$ by $\land$ , each $\land$ by $\lor$ , each $\def\T{{\rm T}}\def\F{{\rm F}}$   $\T$ by $\F$ , and each $\F$ by $\T$ . The dual of $s$ is denoted by $s^*$. Find the dual of these compound propositions.      a) $p \lor\neg q$     I got $\neg p \land q$       b) $p \land (q \lor (r \land \T))$     My answer was $\neg p \lor (\neg q \land r)$       c) $(p \land \neg q) \lor (q \land \F)$     My answer was $(\neg p \lor q) \land  \neg q$  I have tried googling the problem and cannot come up with anything on duals and our lectures are online and upon reviewing do not see anything. I am just confused and looking for a little guidance on what was incorrect with my answers. Line of Bones to Travel and Conform to Curve (Train or snake following path) How to mount read-write an ext4 partition on Windows? I want to use ext4 on my external HDD, but it must be cross-platform. (At least Linux, Win7 &amp; WinXP).  Unfortunately, I haven't found any proper driver allowing Windows to WRITE to ext4. I've found , but it only reads ext4.     9. ext4 extent read-only, no  size truncating and expanding support   More:     Supported Ext3/4 features:         flexible inode size: > 128 bytes, up to block size   dir_index:    htree directory index   filetype:     extra file mode in dentry   large_file:   > 4G files supported   sparse_super: super block backup in group descriptor   uninit_bg:    fast fsck and group checksum   extent:       reading, writing with no extending.   journal:      only support replay for internal journal         Unsupported Ext3/4 features:         journal: log-based operations, external journal   extent: size truncating &amp; expanding, file deletion   flex_bg: first metadata group   EA (extended attributes), ACL support      Also, I have found a patch for Ext4Fsd v0.50 ():     New: Matt Wu has made a new release 0.50 at   ext2fsd.com.  Support for ext4 extents and fix   for BSOD on Windows 7.   I don't think it will be safe. Also I've read some words about writing ext4 in Windows could cause data loss on the disk...  What is the External HDD used for? - First, it will store backups, then family movies, pictures. Some music, and etc. It will be connected to a Raspberry Pi, if I finally receive it. It won't really move, just when it is used to migrate computer's data to a new one. The largest files it will store are Clonezilla disk images (I don't know, if they will be large files or not).  Can someone provide a solution for this problem? Or is there NO important enough difference between ext4 and ext3, and I should use ext3? - (If yes, then can I use Ext2Fsd for that ext3 mount?)  Thank you! Printing a file to a printer in Ruby