Pharma Medical is a producer of medical micromotors for worldwide manufacturers of medical and healthcare equipment. Basing on past 12 periods of demand in table below, Pharma would like to determine the next period's production plan. Time Period Micromotors Demand (S, Million) 1 1.7 2.3 3 3.5 2.8 5 2.7 6 3.2 7 4.6 8 3.8 9 3.5 10 4.0 11 4.8 12 5.3 With the use of spreadsheets and solver only, solve the following: (a) For the period 13, forecast with a two-period & four-period simple moving average respectively. (4 marks) (b) For the corresponding MSE values in (a), which method has a more accurate forecast? (4 marks) (c) For the period 13, forecast with a two-period and four-period weighted moving average. (6 marks)