Simple Harmonic Motion of an ideal spring

[Jtappan]

Homework Statement

An ideal spring has a spring constant k = 29 N/m. The spring is suspended vertically. A 1.4 kg body is attached to the unstretched spring and released. It then performs oscillations.
(a) What is the magnitude of the acceleration of the body when the extension of the spring is a maximum?
____ m/s2
(b) What is the maximum extension of the spring?
____ m

Homework Equations

a$$_{m}$$=$$\frac{k}{m}$$A

The Attempt at a Solution

I don't know how to start this problem. Any help?

 

[Kurdt]

What are the forces acting on the mass. To work out what the acceleration is you need to find the net force at the maximum extension.