A vertical dam has a semicircular gate as shown in the figure. The total depth d of the figure is 30 m, the height h of air above the water level is 6 m, and the width w of the gate is 8 m. Find the hydrostatic force (in N) against the gate. (Round your answer to the nearest whole number. Use 9.8 m/s2 for the acceleration due to gravity. Recall that the weight density of water is 1,000 kg/m3.)