[填空题]
Some electric-power companig.ydi*7o6fc5*f)i2llz s jb j pe8xr9 e.*y/ gt.+tedzivo 5 aes use water to store energy. Water is pumped by reversible turbine pumps from a low to a high rpt/a8 de*e +v yg.5xreoi.z9 teservoir. To store the energy produced in 1.0 hour by a 120-MW ($120\times10^{6}$W) electric-power plant, how many cubic meters of water will have to be pumped from the lower to the upper reservoir? Assume the upper reservoir is 520 m above the lower and we can neglect the small change in depths within each. Water has a mass of 1000 kg for every 1$m^3$. $m^3$
