physics
posted by Sarah .
A 0.55 kg object connected to a light spring with a force constant of 20.0 N/m oscillates on a frictionless horizontal surface. If the spring is compressed 4.0 cm and released from rest.
(a) Determine the maximum speed of the object.
(b) Determine the speed of the object when the spring is compressed 1.5 cm.
2 cm/s
(c) Determine the speed of the object when the spring is stretched 1.5 cm.
3 cm/s
(d) For what value of x does the speed equal onehalf the maximum speed?

I don't know (haha im witty)