The file MortgageRates 3.xsx is available here. Refer to the data in MortgageRates3.xlsx which contains average monthly 30-year mortgage rates (in \%) over 82 consecutive months. Jse Solver to determine the weights for a four-period weighted moving average on the data set that minimizes the MSE. (a) What are the optimal values for the weights? (w1,w2,w3,w4)=() (b) Prepare a line graph comparing the weighted moving average predictions against the original data. (c) What are the forecasts (in \%) for the next 2 months using this technique? (Round your answers to two decimal places.)