One end of a light, elastic string, of natural length 1.2m and modulus of elasticity 32N, is attached to a fixed point, B. A particle, P, of mass 1.5 kg, is then attached to the other end of the string. The particle P is held 2m vertically above the point B and then released.

a. Find the acceleration of P when it is 1.5 m above B.

b. Find the kinetic energy of P when it is at the same horizontal level as B.

c. Find the distance below B when the particle first comes to instantaneous rest.