Verified answer

Explanation:

To find the relative velocity of Car A with respect to Car B, we need to consider their velocities and directions.

Car A is moving towards the North with a velocity of 10 km/h.

Car B is moving towards the South with a velocity of 20 km/h.

Since Car A is moving in the opposite direction to Car B, we need to subtract their velocities to find the relative velocity.

Relative velocity = Velocity of Car A - Velocity of Car B

Relative velocity = 10 km/h - (-20 km/h)

= 10 km/h + 20 km/h

= 30 km/h

Therefore, the relative velocity of Car A with respect to Car B is 30 km/h.