In the question, they GIVE you the rate, but they want you to change its units,
from per-hour to per-minute.
When you want to change units of something, multiply it by a fraction that has
the same number on top and bottom but in different units.
Here. Watch closely:
(84 mile/hour) x (1 hour / 60 minutes) = 84/60 = 1.4 mile/minute
In 2 minutes, the car travels (2 x 1.4) = 2.8 miles
