[DpR]

Hand 1 I fold preflop to that player. Jsut becasue you are in a tough spot out of poisition. If it were heads up I might like the play more - but just not a great spot. I think I check fold the flop.

Hand 2 you have to bet the turn. Don't want to give a free card there. No reason to think he has a K.

Hand 3 - eww, this is not a good trend. You can't be giving free cards here. Make this play with AQ here not JJ.

Hand 4 is fine.

Hand 5: eww again this is bad. Bet turn. People are not getting to higher s.d. numbers by playing scared. You make these turn checks when you have Ace high.