In one cycle of an engine, $1\mathrm{.}73$ kJ of energy is absorbed from a hot reservoir at $277$C$,$ and $1\mathrm{.}17$ kJ of energy is expelled to a cold reservoir at $27\mathrm{.}0$C$.$ What is the engine's efficiency? How much work $($in J$)$ is done by the engine in each cycle? What is the power output $($in kW$)$ of the engine if each cycle lasts $0\mathrm{.}302$ s$?$