How to solve the question below?
Q. A light spring is suspended from a rigid support and its free end carries a mass of 0.40 kg,which produces a static extension of 0.60 m in the spring. The mass is pulled down a further 0.60 m and released. The mass then oscillates with simple harmonic motion. By considering all the energy changes involved, calculate the kinetic energy of the mass as it passes through the mid-point of its motion.