a vertical wall separates two different fluids in an open tank. The right side of the tank contains gasoline (SG=0.8) at a depth of 5m. A rectangular gate hinged 5m high and 3m wide is located in the wall and hinged at the bottom. Water is poured on the left side of the tank. determine the height at which the gate starts to open. (Choices: a. 333.13kN, 3.87m; b. 292.67kN, 2.32m; c. 324.1kN, 3.79m; d. 294.3 kN, 3.33 kN; e. 412.01 kN, 2.50m)