Mr. Smith is designing a race where velocity will be measured. Which course would allow velocity to accurately get a winner?
A. a 5 mile course from the center of town heading north to the outskirts of town
B. a 100 meter swim in a 50 meter pool
C. a 2 mile run around a 400 meter track
D. a 10 mile bike course that zigzags through the mountains and back again