$($a$)$ pts$)1\mathrm{.}00kg$ of water at $1400\mathrm{.}0$kPa and $170\mathrm{.}0C$ is adiabatically expanded in a closed

piston$-$cylinder device to $250\mathrm{.}0$kPa with a second law efficiency of $0\mathrm{.}500.$ Determine the actual

work interaction term for this process $(kJ).$ The second law efficiency for an expansion process is

equivalent to that for a turbine. ANSWER $=-11\mathrm{.}7$ kJ