The following time series represents the number of automobiles sold by a car dealership each of the past five months. \begin{tabular}{|c|c|c|c|c|c|} \hline t & 1 & 2 & 3 & 4 & 5 \\ \hline Yt & 7 & 12 & 10 & 15 & 16 \\ \hline \end{tabular} (b) Use simple linear regression analysis to find the parameters for the line that minimizes MSE for this time series. Y^t= (c) What is the forecast for t=6