If the zero level for the gravitational potential energy is selected to be midway down the slope, 5.50 m above point b, find the initial potential energy, the final potential energy, and the change in potential energy as the skier goes from point to ® in the figure. initial kj k) kj final change need ? man use the worked example above to you solve this problem. a 59.0 kg skier is at the top of a slope, as shown in the figure. at the initial point d, she is 11.0 m vertically above point ® (a) setting the zero level for gravitational potential energy at ®, find the gravitational potential energy of this system when the skier is at and then at b. finally, find the change in potential energy of the skier-earth system as the skier goes from point to point