a. Estimate a linear trend model along with a weekend dummy variable that captures the higher sales volume for Fridays and Saturdays. Note: Negative values for regression coefficients should be indicated by a minus sign. Round final answers to 2 decimal places. b. Use the estimated model to forecast the sales for Monday and Friday of week 11? Note: Round coefficient estimates to at least 4 decimal places and final answers to 2 decimal places. \begin{tabular}{|c|c|c|c|} \hline 41 & 6 & Friday & 3729 \\ \hline 42 & 6 & Saturday & 3457 \\ \hline 43 & 6 & Sunday & 2994 \\ \hline 44 & 7 & Monday & 3690 \\ \hline 45 & 7 & Tuesday & 3559 \\ \hline 46 & 7 & Wednesday & 5102 \\ \hline 47 & 7 & Thursday & 3436 \\ \hline 48 & 7 & Friday & 4278 \\ \hline 49 & 7 & Saturday & 5150 \\ \hline 50 & 7 & Sunday & 4039 \\ \hline 51 & 8 & Monday & 3543 \\ \hline 52 & 8 & Tuesday & 4119 \\ \hline 53 & 8 & Wednesday & 2104 \\ \hline 54 & 8 & Thursday & 3469 \\ \hline 55 & 8 & Friday & 4885 \\ \hline 56 & 8 & Saturday & 5396 \\ \hline 57 & 8 & Sunday & 4504 \\ \hline 58 & 9 & Monday & 4352 \\ \hline 59 & 9 & Tuesday & 4736 \\ \hline 60 & 9 & Wednesday & 3146 \\ \hline 61 & 9 & Thursday & 4561 \\ \hline 62 & 9 & Friday & 5322 \\ \hline 63 & 9 & Saturday & 5359 \\ \hline 64 & 9 & Sunday & 3743 \\ \hline 65 & 10 & Monday & 3478 \\ \hline 66 & 10 & Tuesday & 4351 \\ \hline 67 & 10 & Wednesday & 4207 \\ \hline 68 & 10 & Thursday & 4326 \\ \hline 69 & 10 & Friday & 6571 \\ \hline 70 & 10 & Saturday & 5460 \\ \hline 71 & 10 & Sunday & 5752 \\ \hline \end{tabular}