A 45 g golf ball is pushed up a 30° ramp. The ball starts from rest and the length of the surface of the ramp is 5 m. The coefficient of kinetic friction between the surface on the ramp and the ball is 0.1. The force ceases when the ball leaves the top of the ramp and the total horizontal distance travelled by the ball after leaving the ramp is 20 m. What was the magnitude of the pushing force (in N)?