List out how to do it in excel

Instructions: store. The store owner wants to forecast the quarterly sales for the next year . (a) Construct a time series plot. What type of pattern exists in the data? (b) Use dummy variables and the Excel Regression tool to find a multiple regression model that accounts for seasonal effects in the data. (c) Based on this model, estimate the quarterly sales for the fourth year. \begin{tabular}{|c|c|c|c|c|c|} \hline Year & Quarter & Q1 & Q2 & Q3 & Sales \\ \hline 1 & 1 & 1 & 0 & 0 & 71 \\ \hline 1 & 2 & 0 & 1 & 0 & 49 \\ \hline 1 & 3 & 0 & 0 & 1 & 58 \\ \hline 1 & 4 & 0 & 0 & 0 & 78 \\ \hline 2 & 1 & 1 & 0 & 0 & 68 \\ \hline 2 & 2 & 0 & 1 & 0 & 41 \\ \hline 2 & 3 & 0 & 0 & 1 & 60 \\ \hline 2 & 4 & 0 & 0 & 0 & 81 \\ \hline 3 & 1 & 1 & 0 & 0 & 62 \\ \hline 3 & 2 & 0 & 1 & 0 & 51 \\ \hline 3 & 3 & 0 & 0 & 1 & 53 \\ \hline 3 & 4 & 0 & 0 & 0 & 72 \\ \hline \end{tabular}