Energy is conventionally measured in calories as well as in joules. one calorie in nutrition is one kilocalorie, defined as 1 kcal = 4 186 j. metabolizing 1 g of fat can release 9.00 kcal. a student decides to try to lose weight by exercising. he plans to run up and down the stairs in a football stadium as fast as he can and as many times as necessary. to evaluate the program, suppose he runs up a flight of 95 steps, each 0.150 m high, in 64.5 s. for simplicity, ignore the energy he uses in coming down (which is small). assume that a typical efficiency for human muscles is 20.0%. therefore when your body converts 100 j from metabolizing fat, 20 j goes into doing mechanical work (here, climbing stairs). the remainder goes into extra internal energy. assume that the student's mass is 65.0 kg.