A 2-kg block is dropped from a height of 1.5 m above the end of a vertical uncompressed spring, the force constant of which is 100 N/m. The block strikes the spring, compresses it and then rebounds.

1. What is the potential energy of the block (with respect to the end of the spring) just before it is dropped?
2. What is the kinetic energy of the block when it descends 0.50 m?
3. What is the maximum compression of the spring?
4. How high from the uncompressed spring did the block rise as it rebounds?