A car can go from 0 - 60mi/h in 3 seconds during free fall. How long will it take for this same car to go from 0 - 4 mi/h?

This is hypothetical situation.

a= deltav/time= 60mi/hr/3 sec

Vf=at
4mi/hr= 20mi/hr*sec * t
t= 4/20 of a second.