Live 2/5 game, playing 6 handed at the moment. I raise to $20 UTG (= BTN-3) with X Y. HJ, CO, SB, and BB all call. HJ and CO are good players, both big winners in the game. SB is bad but not awful (a bit too loose, not much of a hand reader at all), while BB is not very good (he's a thinking player, but generally misses out on some chances to make good plays while he makes a few spazz overplays now and then).
Flop comes 9 9 3. Checked to me, I bet $40, HJ and CO fold, SB calls, BB folds.
Turn is the 6. SB bets $100, I call.
At this point, I should tell you that SB now has $850 behind and I cover him.
River is the A. SB bets $200. What is my range of hands if
(a) I fold?
(b) I call?
(c) I raise $275 more?
(d) I raise $650 more (putting him all-in)?
(If it helps you determine my preflop range, I was about $1500 deep to start the hand, HJ and CO both had me covered or nearly so, BTN -- a tightish mediocre player as far as I could tell -- had about $650, SB had about $1000 to start the hand and BB had about $800.)