A village maintains a large tank with an open top, containing water for emergencies. The water can drain from the tank through a hose of diameter 6.55 cm. The hose ends with a nozzle of diameter 2.00 cm. A rubber stopper is inserted into the nozzle. The water level in the tank is kept 7.50 m above the nozzle.
(a) Calculate the friction force exerted by the nozzle on the stopper.
_______________. N
(b) The stopper is removed. What mass of water flows from the nozzle in 2.00 h?
____________kg