The water level in a retention pond started at 5 ft and decreased at a rate of 2 inches a day during a 14 day drought . A tropical depression moved through at the beginning of the 15th day and produced rain at an average of 2.5 inches a day for 5 days . Write a piecewise-defined function to model the water level in inches as a function of the number of days "x" since the beginning of the drought