Assume no reads.

Full Tilt No-Limit Hold'em, $1 BB (6 handed) Hand History Converter Tool from FlopTurnRiver.com (Format: FlopTurnRiver)

UTG ($25.70)
MP ($104.85)
CO ($114.30)
Button ($40.75)
SB ($92)
Hero ($190.20)

Preflop: Hero is BB with A, 3.
UTG calls $1, 1 fold, CO raises to $4.5, Button calls $4.50, 1 fold, Hero ???