Refer to the gasoline sales time series data in the given table. a. Compute four-week and five-week moving averages for the time series. Round your answers to two decimal places. a. Compute four-week and five-week moving averages for the vime series. Round your answers to two decimal places. \begin{tabular}{|c|c|c|c|} \hline Week & Sales & \multicolumn{1}{|c|}{ 4-Week Moving Average } & \multicolumn{1}{c|}{ S-Week Moving Average } \\ \hline 1 & 17 & & \\ \hline 2 & 21 & & \\ \hline 3 & 18 & & \\ \hline 4 & 22 & & \\ \hline 5 & 18 & & \\ \hline 6 & 15 & & \\ \hline 7 & 21 & & \\ \hline 8 & 18 & & \\ \hline 9 & 21 & & \\ \hline 10 & 20 & & \\ \hline 11 & 15 & & \\ \hline 12 & 23 & & \\ \hline \end{tabular} b. Compute the MSE for the four-week and five-week moving average forecasts. Round your intermediate calculations and final answers to two decimal places. Mse for four-week moving average = MSE for five.week meving average =