Ok so my problem was: A 80 kg hiker starts at an elevation of 1600 m and climbs to the top of a 3600 m peak. (a) What is the hiker's change in potential energy? J (b) What is the minimum work required of the hiker? J (c) Can the actual work done be more than this? YES!! so i figured out a) Change in PE = mg(y2-y1) =80kg(9.8 m/s^2)(3600m-1600m) = 1.56 x 10^6 Joules B) Part b is the same answer cause with your PE you can perform minimum work But for C i dont understand how the actual work be more than delta PE?