Answer:
B) 63,360 ft in 1 hour
Explanation:
A) 2.4 mi in 15 min so 2.4 * 4 = 9.6 miles/hour < 10 miles / hour (Answer: No)
B) 63,360 ft in 1 hour = 63,360/5,280 = 12 miles / hours > 10 miles / hour (Answer: YES)
C) 3.8 mi in 45 min = 60 * 3.8 / 45 = 5.01 miles / hour < 10 miles / hour (Answer: No)
D) 21,120 ft in 0.5 hour = 21,120 / 5280 * 2 = 8 miles / hour < 10 miles / hour (Answer: No)