A pendulum is suspended from the ceiling and attached to a spring fixed at the opposite end directly below the pendulum support (Figure). The mass of the pendulum bob is m, the length of the pendulum is L, and the spring constant is k. The unstretched length of the spring is L/2 and the distance between the bottom of the spring and the ceiling is 1.5L. The pendulum is pulled aside so that it makes a small angle ? with the vertical and is then released from rest. Obtain an expression for the speed of the pendulum bob when ? = 0.