In order to calculate velocity, we would need to know where the car was
when it started out, and where it was when it stopped. Without any of this
information, the best we can do is calculate its average speed.
Average speed = (distance covered) / (time to cover the distance)
= (50 miles) / (2.5 hours)
= (50 / 2.5) mile/hour
= 20 mile/hour .