In the figure, a 0.24-kg ball is suspended from a very light string 9.79 m long and is pulled slightly to the left. As the ball swings without friction through the lowest part of its motion it encounters an ideal massless spring
attached to the wall. The spring pushes against the ball and eventually the ball is returned to its original starting
position. Find the time for one complete cycle of this motion if the spring constant of the spring is 21 N/m.