A 0.5 kg sphere A is dropped from a height of 0.6 m onto a 1.0 kg plate B, which is supported by a nested set of springs and is initially at rest. The coefficient of restitution between the sphere and the plate is e=0.8. Determine (a) the height h reached b the sphere after rebound (b) the constant k of the single spring equivalent to the given set if the maximum deflection of the plate is observed to be equal to 3h.