how to do 8b?

8. A small wind turbine has a maximum power output of 1.8 kW at the rated speed of 10 m/s and a rotor diameter of 3 meters. The wind turbine has cut-in and cut-out speeds of 2 m/s and 12 m/s. Assume an air density of 1.2 kg/m'. (a). What is the power coefficient of this wind turbine at maximum power output? [7 marks] (b). If this wind turbine is placed in a site with wind blowing half of the time at I m/s and half of the time at 9 m/s, what is the capacity factor of the wind turbine at this site? Assume power coefficient is the same at all wind speed as that derived in (a). [7 marks] (c). Suppose the turbine costs $5,000, requires no maintenance cost and can operate for 105 hours (about 10 years) at the site discussed in (b). A competing source of electricity costs $0.15/kWh. Does it make economic sense to purchase and install this wind turbine to provide electricity instead of buying electricity from the competing source? 6 marks]