The table named "Sales" to the right, shows the sales of a supermarket (in thousand dollars) in the last 12 months. Note: to facilitate answering the questions in the next two sheets, use Exoel Data Analysis Tool Pack (except for questions 1b and 2d). A B C D E F G H J K L M N O P Q Q2 20 Marks W NH a) Use a = .2 to compute the exponential smoothing forecast for the supermarket sales. 5 Marks 6 b) Use a = .3 to compute the exponential smoothing forecast for the supermarket sales. 5 Marks 8 c) Use a = .4 to compute the exponential smoothing forecast for the supermarket sales. 5 Marks 9 10 d) Does a smoothing constant of .2, .3 or .4 appear to provide more accurate forecasts based on MSE? Explain. 5 Marks Note: show your MSE calculations. 12 13 14 15