A person with a remote mountain cabin plans to install her own hydroelectric plant. A nearby stream is 3.00 m wide and 0.500 m deep. Water flows at 1.35 m/s over the brink of a waterfall 4.20 m high. The manufacturer promises only 25.0% efficiency in converting the potential energy of the water-Earth system into electric energy. Find the power she can generate. (Large-scale hydroelectric plants, with a much larger drop, can be more efficient.)