Hand #1: Most donks are afraid of flushes it seems. I would just call because I don't think you're getting paid off by a lesser K or AA here anyway. But I could see the merrit in raising. You have a better idea of how bad this guy is anyway. I don't call the push though, unless the variety of hands you've seen him show down are completely retarded air bluffs. But these weak $10 bets look like a donk trying to block to a cheap flush. Then on the river he's just doing it again because he's expecting you to raise again.

Hand #2: You can't call this, all you beat is A3 or a bluff. I go for the c/c to get the cheap showdown against a better hand and to induce the bluff from lesser hands myself.

Hand #3: Looks like J9 hit. I could see a 48/23 calling with that UTG. Gotta fold. It could be T8 but I really don't think he makes it to the river with that. Still, I don't think someone that passive raises on the river with a shitty two-pair.

Hand #4: He's a ggressive but does he 4-bet preflop a lot? And if he does, does he push AK or bet it small like this? If you don't know I think you have to fold preflop. If you give him a wide enough 4-betting range to make the call this is the flop you were looking for, gotta get it in.