Month Sales Month Sales Months Sales January 24 May 27 September 29 February 23 June 22 October 21 March 28 July 26 November 28 April 22 August 20 December 23 Use the last-value method retrospectively to determine what the forecasts would have been for the last 11 months of last year. What are MAD and MSE? Use the averaging method retrospectively to determine what the forecasts would have been for the last 11 months of the year. What are MAD and MSE? Use the moving-average method with n = 3 retrospectively to determine what the forecasts would have been for the last nine months of last year. What are MAD and MSE