First hand: He's not folding to your turn c/r, so it's either a monster, a draw, or a K who thinks he's got showdown value 3-handed. I'd like a c/c or c/f at the river, I don't see value in a blocking bet.

Second hand: You have room to raise to 40-45. Don't call though, you're usually behind to TT-KK if he doesn't have the A. If you want to make a move, do it at the flop. His stack size makes a raise to 40 a pressure point for him(which is profitable generally).