Solve each part of given question:

Question: A mass less spring with force constant k = 225 N/m is oriented horizontally and fixed on one end. A 5.00-kg block of ice is placed against the spring on the other end and compresses the spring 3.5 cm. The spring is released and accelerates the block along a horizontal surface. Ignore friction.

Part A: Calculate the work done on the block by the spring during the motion of the block from its initial position to where the spring has returned to its uncompressed length.

Part B: What is the speed of the block after it leaves the spring?

I want help to determine the speed of the block after it leaves the spring.