Hoping to rebound from their loss to the Cardinals, the Bengals stayed at home, donned their alternate uniforms, and played a Week 12 duel with the Tennessee Titans.  In the first quarter, Cincinnati pounced first with RB Rudi Johnson getting a 5-yard TD run for the only score of the period.  In the second quarter, the Titans answered with kicker Rob Bironas getting a 28-yard field goal.  Fortunately, the Bengals responded with QB Carson Palmer completing a 10-yard TD pass to WR Chad Johnson.  Tennessee would end the half with Bironas nailing a 23-yard field goal. In the third quarter, Cincinnati began to pull away as RB Kenny Watson managed to get a 6-yard TD run, while Palmer hooked up with Chad Johnson on a 2-yard TD pass.  In the fourth quarter, the Bengals sealed the victory with Palmer hooking up with Chad for the third time on a 3-yard TD pass. Chad Johnson (12 receptions for 103 yards and 3 touchdowns) ended the game as the Bengals' All-Time receptions leader with 531.  Also, this marked the third time in his career that he caught 3 touchdown passes in one game.
Question: How many field goals did Rob Bironas make in the first half?
Answer: 2