Are gasoline prices higher during the height of the summer vacation season than at other times? The file GasPrices contains the mean monthly prices (in $/gallon) for unleaded gasoline in the

United States from January 2006 to June 2015. (Data extracted from U.S. Energy Information Administration, www.eia.gov/ totalenergy/data/monthly/pdf/sec9_6.pdf.)

a. Construct a time-series plot.

b. Develop an exponential trend forecasting equation with monthly components.

c. Interpret the monthly compound growth rate.

d. Interpret the monthly multipliers.

e. Write a short summary of your findings.