A father pushes horizontally on his daughter's sled to move it up a snowy incline, as illustrated in the figure, with h = 3.8 m and ? = 18°. The total mass of the sled and the girl is 35 kg and the coefficient of kinetic friction between the sled runners and the snow is 0.20. If the sled moves up the hill with a constant velocity, how much work is done by the father in moving it from the bottom to the top of the hill?