PLEASE HELP ME Calculate the speed of a 500 kg racecar that is traveling on a circular track with a radius of 450 meters if the centripetal force that keeps it moving in a circle is 711N.

This energy transformation diagram represents the energy of a skateboarder moving along a half-pipe. as she skates toward the top of the half-pipe, her original kinetic energy is converted to potential energy and friction. how much of the energy is potential?