$55: What to do on river if Villian bets 1) 1/4pot 2) 2/3pot 3) check?

[AA suited]

lvl3, no reads, 8 players left, all ~1250 stacks

folded to Hero in co with A [img]/images/graemlins/diamond.gif[/img] J [img]/images/graemlins/spade.gif[/img]
Hero raises 3BB to 150, sb folds, bb calls

flop (pot=325): 4 [img]/images/graemlins/spade.gif[/img] 7 [img]/images/graemlins/diamond.gif[/img] 9 [img]/images/graemlins/diamond.gif[/img]
bb checks, Hero bets 175, bb calls

turn (pot=675): 5 [img]/images/graemlins/spade.gif[/img]
bb checks, Hero checks

river (pot=675): 9 [img]/images/graemlins/heart.gif[/img]

What would you do if:
1) BB bets out 150?
2) BB bets out 400?
3) BB checks?

And why?