A weight lifter manages to lift a 147 kg weight a distance of 1.1 m. Treat her as a thermodynamic system and find how much heat (in kcal) she must put out if her internal energy decreases by 3620 J during the lift.

147*9.81 * 1.1 = 1586 useful work done

3620 -1586 = heat wasted = 2033 Joules

convert those Joules to kilocalories by typing 2033 Joules = kilocalories into a Google search box and get 0.486 kilocalories