Hand 1: Scary flop, I would bet half pot and get out if raised
Hand 2: Reraise, I would think I was ahead here
Hand 3: Why check the flop?!? Hm....he overbets the flop with no flush draw, so he might be bluffing or is playing AQ and putting you on AK. But with QQQ I think this would be a smart bet also, since KK or AA might put him on a bluff. Would need a read here! I would consider a fold, but, with a good read based on his preflop play I think I would push all in.