My Facebook and Twitter accounts are linked. If I edit a published post in Facebook, will those edits be reflected in Twitter? Or do I manually need to make those changes to the tweet?

No, but it will go somewhere near the top of the page.

Tumblr currently offers no direct way to see if a post by another user has been edited. But if a post is reblogged, and the original post is then edited,...

If you edit your original post after I've reblogged it, my reblog won't be changed because it's an independent post from yours, but if someone else comes along now and...

Yes. However, most libraries will be flexible and accept self-published books that are of good quality, especially if they are of local interest. Make sure that you are speaking to...

The limits are the same for a tweet that originated on Twitter. If you exceed it, the rest will be parsed.

No, I am in Canada and once linked my Canadian bank account to PayPal.

Yes. There should be a key hole to use your key in. By using the handle from the inside, it always unlocks unless there is child safety lock on.

I use NoCrop and Eraser for editing, but for saving videos and story i use InstaDownloader and StorySaver.

Sometimes Twitter limits on tweets, direct messages and followers per day to reduce spammers and reduce error pages. Read How to Get Out of Twitter Jail.

The reply should automatically show up on your homepage. No need to select a special setting.