A dam is inclined at an angle of 30° from the vertical and has the shape of an isosceles trapezoid 80 ft wide at the top and 40 ft wide at the bottom and with a slant height of 70 ft. Find the hydrostatic force on the dam when the water level is at the top of the dam. (Round your answer to the nearest whole number. Assume that the weight density of this water is 62.5 lb/ft3.)