Math...word problem, need help majorly. please:]?

[christina P]

Zoey is at summer camp. One day she is swinging on a rope tied to a tree branch by a river swinging back and forth alternately over land and water. Nathan starts a stopwatch and notes that at x=2 seconds, zoey is at one end of her swing, y= -23 feet from the river bank (over land). When x = 5 seconds, Zoey is at the other end of her swing, y = 17 feet from the river bank (over water) . Assume that as she is swinging, y varies sinusoidally with x.

A) Write the equation to describe Zoey's swinging motion and sketch its graph

B) find y when x = 13.2 seconds. What zoey over land or water at this time?

C) find the first positive time x when zoey was directly over the river bank (y = 0)

D) Zoey lets go of the rope and splashes into the water. What is the value of y for the end of the rope when it comes to rest?