It's easy!but help..
question:at point F the marble doesnt have the same amount energy as it had at the start, where has the energy gone?

The marble as lost energy due to gravity, air resistance (if there is air), and the centripetal force when going around that loop.

Explanation:

Also a little in heat but that rly doesnt matter

"i have always loved contemporary art and made it a general goal to work within the field. after a few nonprofit internships at museums and galleries, i decided to try the for-profit art world and was offered a job as the ad assistant at the magazine. i much prefer the pace of the for-profit art community and have stayed with the company for three years, with a promotion to an account manager last spring."

i just did this and got a 100.

force tends to be low and long diustance masses are high