Suppose that you are on the beach on December 25th and notice high tide occurs at 2:00 pm with a depth of 1.9 meters. You then return at 8:00 in the evening and notice it is low tide at 0.5 meters . Find a cosine function that represents the depth as a function of time in hours that has elapsed since 12:00 midnight at the beginning of December 25th. Assume that the depth varies sinusoidally with time. Find a sine equation, with amplitude, midline, and period.