Using data from $5$ observed weeks of sales, you will create forecasts for the $6$ th week using two methods. The cells in orange help you answer the questions in the assignment. The cells in yellow need to be filled in order to be able to compute the values in the orange cells.

Part $1$: Use a $2-$week moving average forecast $)=(2$

$\backslash$table$[[$Week$,$Actual Sales,Predicted Sales,Forecast Error Abs error,Error $^2,$Abs $\%$ Error$],[1,18,,,,],[2,13,,,,],[3,16,,,,],[4,11,,,,],[5,17,,,,],[6,,,$MAD,MSE,MAPE$],[,,,,,]]$

Part $2$: Use an exponential smoothing forecast with alpha $=0\mathrm{.}8$

Week Actual Sales Predicted Sales Forecast Error Abs error Error ${?}^{{?}^{{?}^{?}}}2$ Abs $\%$ Error