The sales of a company in 4 years are given in the table below: Year Sales 1 851 2 874 3 854 4 867 (a) Copy the following table below into your answer sheet and complete it by using the two-parameter exponential smoothing with a = 0.2 and y = 0.4 to forecast value for the year 5. Show your calculation steps clearly. t Yt Tt bt Ft (Yt - Ft) 1 2 3 4 5 Total (b) (C) Calculate the mean squared error. Which method of forecasting is better single parameter smoothing or two parameters smoothing? Justify your answer. The sales of a company in 4 years are given in the table below: Year Sales 1 851 2 874 3 854 4 867 (a) Copy the following table below into your answer sheet and complete it by using the two-parameter exponential smoothing with a = 0.2 and y = 0.4 to forecast value for the year 5. Show your calculation steps clearly. t Yt Tt bt Ft (Yt - Ft) 1 2 3 4 5 Total (b) (C) Calculate the mean squared error. Which method of forecasting is better single parameter smoothing or two parameters smoothing? Justify your