Location of designated spot throw in for B1?

[IamKip]

Here is a question to all. Let see how many of you can get this one correct. I was surprised by the answers. Where does B1 bring the ball in at?

1.) A1 endline throw-in ball goes out of bounds mid court untouched:
2.) A1 endline throw-in ball goes out of bounds and is caught by A2 who has both feet out of bound:
3.) A1 endline throw-in ball goes out of bounds and hits referee who has both feet out of bounds:
4.) A1 endline throw-in ball goes out of bounds and hits referee who has one foot in bounds and one foot out of bounds:
5.) A1 endline throw-in ball goes out of bounds and hits A2 who has one foot in bounds and one foot out of bounds:

Iamkip