A car with a mass of 1000 kg is on a country road which has its ups and downs or maxima and minima in height. Right now it is at the top of a bump (a maximum) that has a radius of curvature of R = 20 m. What is the maximum speed at which the car can maintain road contact at the bump? If next it is at the bottom of a dip ( a minimum) of the same radius, moving at the same speed, what force does the ground exert on the car?