[adanthar]

1)Without a read I always call here and probably also call with TT. It's made me more chips than it's lost.
2)Generally, if the bet is big enough to mean business I fold here. If it's a minbet I'll raise 2/3 the pot or so.
3)I always bet ~2/3 the pot heads up no matter what the board unless the flop is something weird like QJT.