a) A reservoir, Figure 4, is circular in plan and the sides slope at an angle of tan- (1/5) to the horizontal. When the reservoir is full the diameter of the water surface is 50 m. Discharge from the reservoir takes place through a pipe of diameter 0.65 m, the outlet being 4 m below top water level. Determine the time for the water level to fall 2 m assuming the discharge to be 0. 75a 2gH m'/s where ais the cross sectional area of the pipe in m and His the head of water above the outlet in m. 50m H Figure 4: To be used for Que. Sa b) Using continuity and the Bernoulli equation, derive the expression that can be used to measure actual flow rate with a Venturimeter.