A 52 kg skier is at the top of a slope, as in the

Question

figure. At the initial point A, the skier is 12.4 m vertically above the final point B.
The acceleration of gravity is 9.81 m/s2 .Find the difference in potential energy if
the zero level is midway down the slope, at a
height of 6.20 m.
Answer in units of J.

Answer 1

The difference in potential energy between A and B does not depend upon where you define the zero level to be.

It is M g H, where H is the vertical distance between the two positions.

It is not clear if they are asking for the PE difference between A and B or between A and the midway point.