Answer: 10.5 inches or .875 feet.
Explanation:
First calculate the SPEED = Distance /Time. So 1/2 of a foot = 6 inches so distance of 6 inches divided by time of 4 sec = s 1.5 (inches) per sec. So using Distance = speed x time we calculate 1.5in x 7 sec= a distance of 10.5 inches or 10.5 inches divided by 12in that is in a foot = .875 feet.