Q1.The quarterly sales levels (measured in millions of dollars) for Goodyear Tiresare shown in the above Table.

A.Does there appear to be a significant seasonal effect in these sales levels? Plot the time series.

B.Perform the decomposition analysis using multiplicative & additive models .

C.Analyze this time series to get the four seasonal Indexes and interpret the indexes and determine the extent of the seasonal component in Goodyear's sales?

D.Forecastsales for the four quarters of 2007 for each model and compare the result& comment on them.

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