What is the distance traveled in feet after 12 seconds at 87 miles per hour?

1 mile = 5,280 ft

87 miles in 1 hour = 87(5,280 ft) in 3,600 seconds = 459,360 ft. That is 127.6 ft in 1 second.

So in 12 seconds the distance traveled will be 1,531.2 ft (12 x 127.6)