The followings are some export records of an independent administrative region (IAR) of a year: Month January 1 February 2 March 3 April 4 May 5 June 6 July 7 August 8 September 9 October 10 November 11 December 12 Export ($ billion) 31.64 27.13 33.17 32.22 31.98 32.53 33.09 33.50 34.46 37.20 33.24 38.71 (a) Forecast the export in January of the year after by using simple moving average of 4 periods. (b) Forecast the export in January of the year after by exponential smoothing using Ft = Ft-1+ (At-1 - Ft-1) with a = 0.5 and first forecast = actual record. (c) Forecast the export in January of the year after by linear regression using F(t) = a + b(t). (4) Determine the best forecast among the results obtained in (a), (b), (c).