$1.$ The gas turbine uses $3$ kg $/$ s of hot air, which enters with pressure and heat of $4$ bar, $760\backslash$deg C$,$ exits the exhaust at $400\backslash$deg C and produces heat losses from the generator body of $15$ kW$.$

$2.$ The air temperature is $1005$ J $/$ kg$.$ K$,$ the kinetic energy and the potential energy were neglected.