A natural waterfall, $50$ meters high, consistently

discharges $1\mathrm{.}3$ m$3$ per second. A mini hydroelectric

plant is to be constructed at the bottom of the

waterfalls. Calculate the annual energy in kW$-$hr that

can be generated by the power plant. Assume turbine

and generator efficiencies equal to $70\%$ and $90\%,$

respectively.

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