Assume you collected a quarterly sales data (in millions of dollars) over a four-year period from the first quarter 2016 to the fourth quarter 2019, and computed the seasonal index for

each quarter. If the (normalised) seasonal index for the first quarter is 1.04, then we can interpret it as follows. a. In the first quarter, sales are 4% above the annual average. b. There is a 1.04% difference in sales between the first quarter and the fourth quarter. C. In the first quarter, sales are 1.04% above the annual average. d. There is a 4% difference in sales between the first quarter and the third quarter.