If one was on a pogo stick, and they were able to hop up 6" , what would it take to hop up 60" ?

The speed coming down will always be the same. And the riders weight can never change. The rider must start on the ground each time. The travel of the sliding parts can only increase by 1/4 of it's original travel length.

If a 50-pound bag of sand was dropped from a height of 2 feet and that same bag was dropped at 6 feet, would the force hitting the ground be the same?

If you had two 25 pounds of sand, and both were dropped from the same height, but hit the ground just a millisecond apart. Would the total force be different and how?