A 1500-kg car enter an S-curve at A with a speed of 96 km/h with brakes applied to reduce the speed to 72 km/h at a uniform rate in a distance of 90 m measured along the curve from A to B. The radius of the curvature of the path of the car at B is 180 m. Calculate the total friction force exerted by the road on the tires at B. The road at B lies in a horizontal plane.