A 1,990-kg automobile starts from rest at point A on a 7degree incline and coasts through a distance of 143m to point B. The brakes are then applied, causing the automobile to come to a stop point C, 19m from B. Knowing that slipping is impending during the braking period and neglecting air resistance and rolling resistance, determine (a) the speed of the automobile at point B, (b) the coefficient of static friction between the tires and the road.