Refer to the gasoline sales time series data in the given table.

Week Sales (1,000s of gallons)

1 18

2 22

3 15

4 24

5 18

6 15

7 21

8 19

9 21

10 20

11 16

12 22

(a) Compute four-week and five-week moving averages for the time series.If required, round your answers to two decimal places.

Week Sales 4 PeriodMoving 5 periodMoving

Average Average

1 18

2 22

3 15

4 24

5 18 ______________

6 15 ______________ _____________

7 21 ______________ _____________

8 19 ______________ _____________

9 21 ______________ _____________

10 20 ______________ _____________

11 16 ______________ _____________

12 22 ______________ _____________

(b) Compute the MSE for the four-week and five-week moving average forecasts.If required, round your final answers to three decimal places. MSE for four-week moving average =MSE for five-week moving average =____________________________________________

(c) What appears to be the best number of weeks of past data (three, four, or five) to use in the moving average computation? Consider that the MSE for the three-week moving average is 10.086

.- Select your answer below -

• Three
• Four
• Five