A starting pitcher who is removed cannot re-enter in either league, if he is removed from the game. It's rarely if ever done in Major League Baseball, but if a pitcher is removed as a pitcher but placed in another position he can later return to the pitcher position.
No, once you leave the game you cannot re-enter it, regardless of the positions.
No. Pitchers can re-enter once in Juniors and above, but there is no re-entry as a pitcher in Majors and below in Little League.
If he is skilled enough
No
Only if the pitcher warms up on the diamond.
46 feet
Pat Venditte did, so yeah.
For little league they are usually 46-60 meaning 46 ft from pitcher to catcher and 60 ft from the bases
Honestly, it varies. I've seen short little league pitchers that are the best. But speaking from what experts would say, the upper 5 feet, 5'8, 5'9, etc. Less then that as well, though. If your a little league pitcher, or your son is, don't let the lack of height get you down. Anything is possible.
one game
No, he can not. Since he does not have the ball he will be called for interference.
from 50-80 depending on the pitcher