Year Month Q 2007 January 6,942 2007 February 7,348 2007 March 7,328 2007 April 8,350 2007 May 8,619 2007 June 9,282 2007 July 8,183 2007 August

3. For 2007–2009, Gallaway, Inc. has collected the following data on monthly salesof its Titan II driving club, where Q = the number of units sold per month.Year Month Q Year Month Q Year Month Q2007 January 6,942 2008 January 8,007 2009 January 7,925February 7,348 February 7,698 February 7,326March 7,328 March 7,417 March 8,037April 8,350 April 8,897 April 9,087May 8,619 May 8,607 May 9,303June 9,282 June 9,314 June 9,139July 8,183 July 8,686 July 8,105August 8,317 August 8,539 August 8,321September 8,552 September 8,967 September 8,960October 7,993 October 8,507 October 7,580November 8,198 November 8,359 November 8,562December 8,082 December 8,157 December 8,072a. Management at Gallaway is concerned about sales. They would like to knowif there is an upward trend is sales of the Titan II. Use the data above toestimate the monthly trend in sales using a linear trend model of theform: Qt = a + bt . Does your statistical analysis indicate a trend? If so, is itan upward or downward trend and how great is it? Is it a statisticallysignificant trend (use the 5 percent level of significance)?b. Now adjust your statistical model to account for seasonal variation in clubsales. Estimate the following model of sales:Qt = a + bt + c1D1t + c2D2t + c3D3twhere D1t = 1 for the months of January–March or 0 otherwise, D2t = 1 forthe months of April–June or 0 otherwise, and D3t = 1 for the months ofJuly–September or 0 otherwise. Do the data indicate a statistically significantseasonal pattern (use the 5 percent level of significance)? If so, what is theseasonal pattern of sales of Titan II clubs?c. Comparing your estimates of the trend in sales in parts a and b, whichestimate is likely to be more accurate? Why?d. Using the estimated forecast equation from part b, forecast sales of Titan IIclubs for January 2010, January 2011, July 2010, and July 2011.