The ski lift pulls skiers up the slope for a distance of 310 meters. The slope is at an angle of 15 degrees to the horizontal plane. The maximum speed of the lift is 10 km/h, and it can pull 50 skiers at the same time. Let's assume that the skier's average mass is 67 kg, and that the friction between the skis and the snow becomes small. Estimate how much power the ski lift needs.