After winning on the road, the Bengals returned home for Game 2 of the Battle of Ohio.  In the first quarter, the Browns took an early lead when Zane Gonzalez kicked a 27-yard field goal to make it 3-0.  Though the Bengals took the lead when Andy Dalton found Tyler Boyd on an 8-yard pass to make it 7-3.  In the second quarter, the Bengals increased their lead with 3 straight field goals kicked by Randy Bullock:  From 31, 49, and 21 yards out to make the score 10-3, 13-3, and 16-3.  Gonzalez managed to get the Browns closer with a 21-yard field goal of his own to make it 16-6 at halftime.  In the third quarter, the Bengals pulled away as Dalton found Tyler Kroft on a 1-yard pass to make it 23-6.  Gonzalez managed to put to get the Browns within 2 touchdowns when he kicked his third field goal of the game:  from 39 yards out to make it 23-9.  The Browns came within a touchdown when DeShone Kizer ran for a 3-yard touchdown to make it 23-16.  However, the Bengals sealed the game when Joe Mixon ran for an 11-yard touchdown to make the final score 30-16. Against the Browns, Joe Mixon had a career day, rushing for 114 yards and a touchdown, the first 100-yard game of his young career. With the win and 7th straight over the Browns, the Bengals went to 5-6.
Question: How many field goals were kicked during the first half?
Answer: 5