$.$ New car sales for a dealer in Cook County, Illinois, for the past year are shown in the following table, along with monthly indexes $($seasonal relatives$),$ which are supplied to the dealer by the regional distributor.

a$.$ Plot the data. Does there seem to be a trend?

b$.$ Deseasonalize car sales.

c$.$ Plot the deseasonalized data on the same graph as the original data. Comment on the two graphs.

d$.$ Assuming no proactive approach on the part of management, discuss $($no calculations necessary$)$ how you would forecast sales for the first three months of the next year.

e$.$ What action might management consider based on your findings in part b$?$

$6.$ The following table shows a tool and die company$$s quarterly sales for the current year. What sales

would you predict for the first quarter of next year? Quarter relatives are SR$1=1\mathrm{.}10,$ SR$2=\mathrm{.}99,$ SR$3=\mathrm{.}90,$ and SR$4=1\mathrm{.}01.$