(a) A water tank is 30 ft in diameter, and the normal depth is 25 ft. The outlet is a 4-in, horizontal pipe at the bottom. If this pipe is sheared off close to the tank, what is the initial flow rate of water from the tank? (Neglect friction loss in the short stub of pipe.) 

(b) How long will it take for the tank to be empty? 

(c) Calculate the average flow rate and compare it with the initial flow rate and compare it with the initial flow rate.