I think it would be the sun because it’s the one giving energy to most things, and if you haven’t answered it yet you can put the sun because it’s giving energy to the plans and the environment and it’s the the sun was the effect of the whole thing, sorry if I didn’t help
For a hydrogen atom, composed of an orbiting electron bound to a nucleus of one proton, an ionization energy of 2.18 × 10−18 joule (13.6 electron volts) is required to force the electron from its lowest energy level entirely out of the atom.
Basically, because the skater will never use some kind of a boost, they will rely purely on forces. At the top of a slope, their kinetic E is zero, and their Potential E is as high as it will be.
The skater will not be able to ever get higher that the initial height without some kind of force helping it.
