Apressurized 2-m-diameter tank of water has a 10-cm-diameter orifice at the bottom where water discharges to the atmosphere. the water level initially is 3 m above the outlet. the tank air pressure above the water level is maintained at 450 kpa absolute and the atmospheric pressure is 100 kpa neglecting frictional effects, determine: (a) how long it will take for half of the water in the tank to be discharged; (b) the water level in the tank after 10 s