1) sure you can bet here....there are lots of AX hands and some FD's here that you can bet against.

2) I'm betting about $1.50 so pretty close. If he caught a piece of this he cant fold....

3) Good card to barrel imo, but he called the flop when it was multiway which makes me think he's not going to fold as often here

4) I likely fold to his raise

5) No reason to donk imo. You can call his cbet, you're ahead of his betting range imo.

6) Not sure preflop, dont bet the turn, too many chances for another player to have the flush