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An environmental group is lobbying to shut down a coal-burning power plant that produces electrical energy at the rate of 1 GW (a watt, W, is a unit of power—the rate of energy production or consumption). They suggest replacing the plant with wind turbines that can produce 1.5 MW each but that, due to intermittent wind, average only 30% of that power. Estimate the number of wind turbines needed.
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