(a) Compute four-week and five-week moving averages for the time series. (a) Compute four-week and five-week moving averages for the time series. (b) Compute the MSE for the four-week moving average forecasts. (Round your answer to two decimal places.) Compute the MSE for the five-week moving average forecasts. (Round your answer to two decimal places.) Three weeks appears to be best, because the three-week moving average provides the smallest MSE. Three weeks appears to be best, because the three-week moving average provides the largest MSE. Four weeks appears to be best, because the four-week moving average provides the smallest MSE. Five weeks appears to be best, because the five-week moving average provides the smallest MSE. None appear better than the others, because they all provide the same MSE