The height, h metres, of the water, above a mark on a harbour wall, changes with the tide. It is given by the equation h=3sin (30 t)°, where t is the time in hours after midday.
(a) Calculate the value of h at midday.
Answer
(b) Calculate the value of h at 1900 .
Answer

The height h metres of the water above a mark on a harbour wall changes with the tide It is given by the equation h3sin 30 t where t is the time in hours after class=