Water flows from a tank through a 2.6 m length of galvanized iron pipe 26 mm in diameter. At the end of the pipe is an angle valve that is wide open. The tank is 2 m in diameter. Calculate the time requried for the level in the tank to change from 10 m to 2 m. Develop an equation for dh/dt where h is the level and t is time. Then solve the equation numerically. Water is at 20 degrees celcius, tank is initially at 10 m high, pipe is 2.6 m long.