A circular curve of highway is designed for traffic moving at 96 km/h. Assume the traffic consists of cars without negative lift. (a) If the radius of the curve is 180 m, what is the correct angle of banking of the road? (b) If the curve were not banked, what would be the minimum coefficient of friction between tires and road that would keep traffic from skidding out of the turn when traveling at 96 km/h?