4. What is the maximum power transfer of a spring with force constant k to an attached object in a simple harmonic oscillation with amplitude A and frequency f?___(5)___

5. The following metal objects, a disk, a solid sphere, a hollow sphere, and a loop have the same radius and mass. Assuming they are released from the same point on a ramp at rest and start rolling down, which one will take the shortest time to reach the bottom of this ramp? ___(6)___