If a tire rotates at 400 revolutions per minute when the car is traveling 24km/h, what is the circumference of the tire?  Choose the correct option.
A) 1 meters B) 6 meters C) 5 meters D) 3 meters E) 7 meters

Rationale: "400 rev / minute = 400 * 60 rev / 60 minutes = 24,000 rev / hour 24,000 * c = 24,000 m : c is the circumference c = 1 meters correct answer a"
Answer: A