The height, h, of a buoy on a boating lake can be modelled by h = 0.25 sin (1800t)°, where h is the height in metres above the buoy’s resting position and t is the time in minutes.

a. State the maximum height the buoy reaches above its resting position according to this model.

b. Calculate the time, to the nearest tenth of a second, at which the buoy is first at a height of 0.1 metres.

c. Calculate the time interval between successive minimum heights of the buoy.