a gate having the cross section shown in figure closes an opening 5 ft wide and 4 ft high in a water reservoir.

a gate having the cross section shown in figure closes an opening 5 ft wide and 4 ft high in a water reservoir. the gate weighs 500 lb and its center of gravity is 1 ft to the left of AC and 2 ft above BC. Determine the horizontal reaction that is developed on the gate at C