As shown in Fig. 11-4, a long, light piece of spring steel is clamped at its lower end and a 2.0-kg ball is fastened to its top end. A horizontal force of 8.0 N is required to displace the ball 20 cm to one side as shown. Assume the system to undergo SHM when released. Find (a) the force constant of the spring and (h) the period with which the ball will vibrate back and forth.