Please help me out! thank you

Vacation destinations often run on a seasonal basis, depending on the primary activities in that location. Amanda Wang is the owner of a travel agency in Cincinnati, Ohio. She has built a database of the number of vacation packages (Vacation) that she has sold over the last 12 years. The accompanying file includes quarterly data on the number of vacation packages sold. Click here for the Excel Data File a. Estimate the linear regression models using seasonal dummy variables with and without the trend term. Which is the preferred model? b. Use the preferred model to forecast the quarterly number of vacation packages sold in the first two quarters of 2020. Note: Round coefficient estimates to at least 4 decimal places and final answers to 2 decimal places. \begin{tabular}{|r|r|r|r|} \hline & A & B & C \\ \hline 1 & Year & Quarter & Vacation \\ \hline 2 & 2008 & 1 & 500 \\ \hline 3 & 2008 & 2 & 147 \\ \hline 4 & 2008 & 3 & 1314 \\ \hline 5 & 2008 & 4 & 673 \\ \hline 6 & 2009 & 1 & 984 \\ \hline 7 & 2009 & 2 & 584 \\ \hline 8 & 2009 & 3 & 1449 \\ \hline 9 & 2009 & 4 & 1125 \\ \hline 10 & 2010 & 1 & 209 \\ \hline 11 & 2010 & 2 & 458 \\ \hline 12 & 2010 & 3 & 1357 \\ \hline 13 & 2010 & 4 & 544 \\ \hline 14 & 2011 & 1 & 483 \\ \hline 15 & 2011 & 2 & 280 \\ \hline 16 & 2011 & 3 & 1392 \\ \hline 17 & 2011 & 4 & 780 \\ \hline 18 & 2012 & 1 & 340 \\ \hline 19 & 2012 & 2 & 1003 \\ \hline 20 & 2012 & 3 & 1692 \\ \hline 21 & 2012 & 4 & 783 \\ \hline 22 & 2013 & 1 & 781 \\ \hline 23 & 2013 & 2 & 409 \\ \hline 24 & 2013 & 3 & 1657 \\ \hline 25 & 2013 & 4 & 792 \\ \hline 26 & 2014 & 1 & 671 \\ \hline 27 & 2014 & 2 & 769 \\ \hline 28 & 2014 & 3 & 1068 \\ \hline 39 & 2014 & 4 & 520 \\ \hline 30 & 2015 & 1 & 616 \\ \hline \hline \end{tabular}