To store the energy produced in 1.5 hour by a 160 MW (160 10^6 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 500 m above the lower and we can neglect the small change in depths within each. Water has a mass of 1000 kg for every 1.0 m^3. Express your answer using two significant figures.