water pressure requirement at the roof

The rectangular tank shown here, with its top at ground level, is used to catch runoff water. Assume that the water weighs 62.3 lb/ft³. a. How much work does it take to empty the tank by pumping the water back to ground level once the tank is full? b. If the water is pumped to ground level with an (8/11)-horsepower (hp) motor (work output 400 ft-lb/sec), how long will it take to empty the tank (to the nearest minute)? c. Show that the pump in part (b) will lower the water level 15 ft (halfway) during the first 20 minutes of pumping. d. What are the answers to parts (a) and (b) in a location where water weighs 62.16 lb/ft³? 62.42 lb/ft³? a. Set up an integral to find the work done. W = Ground 5 ft level 0 30 14 ft

A tank is leaking water at a rate of 1 L every 4 minutes. The tank's base measures 1 m by 90 cm and its height is 45 cm. If it took 21 hours and 36 minutes for the tank to empty, how far below the top of the tank was the original height of the water in the tank?