Avertical spring with spring stiffness constant 305 n/m oscillates with an amplitude of 28.0 cm when 0.235 kg hangs from it. the mass passes through the equilibrium point (y=0) with positive velocity at t=0. positive direction of y-axis is downward.

part a

what equation describes this motion as a function of time?

part b

at what time will the spring stretch to its maximum length at first time?

part c

at what time will the spring shrink to its minimum length at first time?