50nl: Trips on the turn...

[crunchi]

Villain is 50/17/1.5 after about 100 hands. He doesnt seem very good at all.

Poker Stars, $0.25/$0.50 NL Hold'em Cash Game, 6 Players
LeggoPoker Hand History Converter

SB: $49.95
BB: $71.90
UTG: $61
MP: $33.25
CO: $50
Hero (BTN): $47.90

CO posts $0.50
Pre-Flop: A[img]/images/graemlins/club.gif[/img] 3[img]/images/graemlins/club.gif[/img] dealt to Hero (BTN)
UTG folds, <font color="red">MP raises to $2</font>, CO folds, Hero calls $2, 2 folds

Flop: ($5.25) 7[img]/images/graemlins/spade.gif[/img] A[img]/images/graemlins/spade.gif[/img] T[img]/images/graemlins/club.gif[/img] (2 Players)
<font color="red">MP bets $3.50</font>, Hero calls $3.50

Turn: ($12.25) A[img]/images/graemlins/heart.gif[/img] (2 Players)
<font color="red">MP bets $4</font>, Hero????

I dont think villain is aggressive enough to dbl barell light here. I put him on Aces, draws or MAYBE KK, QQ, JJ.
Thoughts on his range and what i should do?