The height of the water in the harbor of a coastal town is a periodic function of time.The height (in feet) is approximated by

h(t)=18+17.8sin(πt/6) , where t is time in hours since midnight.

a.when does high tide occur?what is the water height at high tide?

b.when does low tide occur ? what is the water height at low tide?

c.calculate h'(14).interpret the result in terms of time of day and water height in the harbor.