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

   Week	Sales	4 Period Moving Average	5 Period Moving Average
   1	17
   2	21
   3	19
   4	23
   5	18
   6	16
   7	20
   8	18
   9	22
   10	20
   11	15
   12	22

2. Compute the MSE for the four-week and five-week moving average forecasts. Compute the MSE for the four-week and five-week moving average forecasts. MSE for four-week moving average = fill in the blank 16 MSE for five-week moving average = fill in the blank 17
3. What appears to be the best number of weeks of past data (three, four, or five) to use in the moving average computation? Recall that MSE for the three-week moving average is 10.22.

Problem 6-07 Refer to the gasoline sales time series data in the given table. GASOLINE SALES TIME SERIES Week 1 2 3 4 5 6 7 8 9 10 11 12 Sales (1000s of gallons) 17 21 19 23 18 16 20 18 22 20 15 22