A box with a mass of m = 7.50 kg is set on top of a spring with a spring constant

of k = 500 N/m. The box is pushed down 30.0 cm and released.
(a) What is the maximum height the box reaches after being launched by the
spring?
(b) What is the instantaneous power delivered to the box by the spring when it
is only compressed by 10.0 cm?