. Construct a timeseries graph of the sales data for HeathCo's line of skivvear (see data in 51311 1. Does there appear to be a seasonal pattern in the sales data'.' Explain why you think the results are as you have found {c5pll ] . It seems logical that skiwear would sell better from October through March than from April through September: To test this hypothesis. begin by adding two dulnmy variables to the data: a dummy variable Q] = ] for each first quarter (January. February. March} and Q] = 0 otherwise; and a dummy variable Q4 2 ] for each fourth quarter (October, November. December] and Q4 2 0 otherwise. Once the dummy variables have been entered into your data set, estimate the following trend model: SALES be + fart[TIME] + ngl + b3Q4 Evaluate these results by answering the following: . Do the signs make sense\"? Why or why not\".I . Are the coefficients statistically different from zero at a 95 percent confidence level (onetailed test'J'.j . What percentage of the variation in SALES is explained by this model'.' . Use this model to make a forecast of SALES (S132) for the four quarters of 2017r and calculate the MAPE for the forecast period. Period SALES [$000] SFZ ZUIYQI 334.27] _ 20]?Q2 328.982 _ 20]?Q3 317.92] _ 20]?Q4 350.118 _ (2'. Prepare a time-series plot of SALES (for 200112] through 2016Q4} along with SFZ (for 2007'Q1 through 20]?Q4} to illustrate how SALES and SF2 compare