Blind on Blind: AQ facing minraise

[zooot]

PokerStars Hold'em No Limit ($0.10/$0.25) - 2007/07/24
6-max Seat #6 is the button
Seat 1: HERO ($32.60 in chips)
Seat 2: BB ($54.75 in chips)
Seat 3: UTG ($39.30 in chips)
Seat 4: MP ($25 in chips)
Seat 5: CO($24.30 in chips)
Seat 6: Button($32.65 in chips)
HERO: posts small blind $0.10
BB: posts big blind $0.25
*** HOLE CARDS ***
Dealt to HERO [Q [img]/images/graemlins/diamond.gif[/img] A [img]/images/graemlins/spade.gif[/img]]
UTG: folds
MP: folds
CO: folds
Button: folds
HERO: raises $0.75 to $1
BB: raises $0.75 to $1.75
HERO: calls $0.75
*** FLOP *** [8 [img]/images/graemlins/heart.gif[/img] 9 [img]/images/graemlins/heart.gif[/img] 7 [img]/images/graemlins/club.gif[/img]]
HERO: checks
BB: bets $2.75
HERO: ???

BB is 53/29/1.65/315. VPIP and PFR are high, but villain has not min 3-bet before in this session (~190 hands). Who is 4-betting preflop? Who is leading this flop? Calling? Anything else? Thx