john runs 500 feet in 1 minute. identify the correct conversion factor setup required to compute john's speed in inches per second.

a. 12 inches / 1 foot x 60 seconds / 1 minute
b. 1 foot / 12 inches x 60 seconds / 1 minute
c. 1 foot / 12 inches x 1 minute / 60 seconds
d. 12 inches / 1 foot x 1 minute / 60 seconds