For the following exercises, construct a sinusoidal function with the provided information,

For the following exercises, construct a sinusoidal function with the provided information, and then solve the equation for the requested values.

In a certain region, monthly precipitation peaks at 24 inches in September and falls to a low of 4 inches in March. Identify the periods when the region is under flood conditions (greater than 22 inches) and drought conditions (less than 5 inches). Give your answer in terms of the nearest day.