1) between 50 and 70 should be fine
2) it has something to do with the sum of the bkrs of the players who have fallen in before you and the sum of bkr of the players who are still there when you fall in the pond
3) a pawn cant make a new bet .. so when someone becomes a pawn during a pond .. he will repeat his last bet until he is out of points or until he falls into the pond