The reservoir at Northfield Mountain Pumped Storage Project is 214 m above the pump/generators and holds 2.1 × 1010 kg of water (see Application on p. 113). The generators can produce electrical energy at the rate of 1.08 GW. Find (a) the gravitational potential energy stored, taking zero potential energy at the generators, and (b) the length of time the station can generate power before the reservoir is drained.
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