Hong Kong has the wind power station in Lamma Island.  The maximum height that the wind turbine reaches is 71 m.  The nacelle can adjust the speed of the wind turbine depending on wind directions; however, normally, the wind power rotates 0.6 degree each second.   The rotor blades are 25m long. 

 

a. State peak, trough, amplitude, period and the equation of the x-axis.

b. If a blade starts to rotate from the maximum point, how high will it be from the ground after 45 min?