Hydraulics - Orifice: Situation 2 - Falling Head

Situation 2: A water tank has the form of a right circular cone of diameter 3.66 m and height of 3.66 m is surmounted with a right circular cylinder of the same diameter and having a height of 3.66 m. There is an orifice at the vertex of the cone whose area is 0.0929 m². Initially the tank is full of water. Assume coefficient of discharge C = 0.60. Evaluate the following after the orifice is opened: 4. The time to empty the cylindrical part of the tank. 5. The time to empty the conical part of the tank. 6. The total time to empty the tank.