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10. The BEST company has developed a trend equation which is based on the quarterly sales on its Bluetooth wireless headphone (in 3'000) over the past 3 years is: y = 11.5 + 1. 6t where t = l for quarter 1 of year 1 The following table gives the adjusted seasonal index for each quarter. Using the additive model, complete the below table to determine the trend value and forecast for each of the four quarters of the fourth year (correct to 1 decimal place). Trend value (y) Adjusted Forecast (3'000) seasonal index (S '000) Year Quarter t 4 16 355 5.3