I need some help with this hwk! Please someone help me... A certain spring is found not to obey Hook’s law; it exerts a restoring force if it is stretched or compressed, where α = 60.0 N / m and β = 18.0 N / m2. The mass of the spring is negligible. (a) Calculate the potential-energy function U(x) for the spring. Let U = 0 when x = 0. (b) An object with mass m = 0.900 kg on a frictionless, horizontal surface is attached to this spring, pulled a distance 1.00 m to the right (the + x-direction) to stretch the spring, and released. What is the speed of the object when it is 0.500 m to the right of the equilibrium position? (c) Use Newtonian dynamics to find the speed at this position. (d) What is the instantaneous power when x = 0.500 m?