The file Phone Expenses contains the monthly telephone expenses for a small business.
a. Produce a time-series graph of the data. Can you identify a trend or seasonal component?
b. Using the Excel 2016 Forecast Sheet option, produce a forecast for January 2016.
c. Report the smoothing parameter and the forecast error measurements produced by Excel’s forecast.
d. Use the Excel 2016 forecast function, FORECAST.ETS, to produce a forecast for January 4, 2016. Assume there is no seasonality in the data. 

e. Use the Excel 2016 forecast function, FORECAST. ETS.CONFINT, to compute a 95% confidence interval for the January 4, 2016, forecast for phone expenses.