United Dairies, Inc. supplies milk to several independent grocers throughout Dade county, Florida. Managers at United Dairies want to develop a forecast of the number of half-gallons of milk sold per week. Sales data for the part 10 weeks follow.

Week Sales

1 2750

2 3100

3 3250

4 2800

5 2900

6 3050

7 3300

8 3100

9 2950

10 3000

a. construct a time series plot.

b. Use exponential smoothing with alpha = .4 to develop a forecast of demand for week 11.

c. Calculate the MSE.

d. Use excel to fit a linear trend line through the data.