Question

a man drives Northward at the rate of 80 km/h and then back to his starting point at the rate of 60 km/hr. What is his average velocity?

Answer 1

Velocity =
(distance between start and end points) / (time to cover the distance), and
the direction from start point to end point.

Since the man ends where he started, the distance (displacement) is zero,
and his average velocity is zero.