A wind generator (mass 120 kg) with a 9.15 m-diameter blade span has a cut-in wind speed (the minimum speed for power generation) of 3.13 m/s, at which the velocity the turbine generates 0.4 kW of electric power. Assume p of air as 1.217 kg/m3. Determine (a) the efficiency of wind turbine-generator unit and (b) the reaction force exerted on the wind by the supporting mast of the wind turbine if the frictional effects are disregarded. %3D Streamline utm F, Wgenerator y