a. Calculate the 12-month centered moving average. (Do not round intermediate calculations. Round your answers to 2 decimal places.) Year : 1 Month Jan Feb 1 1 Mar 1 Apr May 1 1 Jun 1 Jul 1 Aug 1 Sep Oct 1 1 Nov Dec 1 Feb 6 5 Mar 5 5 Apr May Jun Jul 5 5 5 5 Aug Sep Oct 5 5 Nov 5 Dec b. Calculate the ratio-to-moving average. (Do not round intermediate calculations. Round your answers to 2 decimal places.) Year Month Ratio-to-Moving Average:yly 1 Jan Feb 1 1 Mar 1 Apr 1 1 May Jun Jul 1 1 1 Aug Sep Oct 1 1 Nov Dec 1 5 Feb 5 Mar 5 Apr May 5 5 Jun 5 Jul 5 5 Aug Sep Oct 5 5 Nov 5 Dec C-1. Calculate the seasonal indices for April and November. (Do not round intermediate calculations. Round your answers to 4 decimal places.) Adjusted Seasonal Index April November c-2. Interpret the seasonal index for April. (Do not round intermediate calculations. Round your answer to 2 decimal places.) The series is % its average monthly level. c-3. Interpret the seasonal index for November. (Do not round intermediate calculations. Round your answer to 2 decimal places.) The series is % its average monthly level. a. Calculate the 12-month centered moving average. (Do not round intermediate calculations. Round your answers to 2 decimal places.) Year : 1 Month Jan Feb 1 1 Mar 1 Apr May 1 1 Jun 1 Jul 1 Aug 1 Sep Oct 1 1 Nov Dec 1 Feb 6 5 Mar 5 5 Apr May Jun Jul 5 5 5 5 Aug Sep Oct 5 5 Nov 5 Dec b. Calculate the ratio-to-moving average. (Do not round intermediate calculations. Round your answers to 2 decimal places.) Year Month Ratio-to-Moving Average:yly 1 Jan Feb 1 1 Mar 1 Apr 1 1 May Jun Jul 1 1 1 Aug Sep Oct 1 1 Nov Dec 1 5 Feb 5 Mar 5 Apr May 5 5 Jun 5 Jul 5 5 Aug Sep Oct 5 5 Nov 5 Dec C-1. Calculate the seasonal indices for April and November. (Do not round intermediate calculations. Round your answers to 4 decimal places.) Adjusted Seasonal Index April November c-2. Interpret the seasonal index for April. (Do not round intermediate calculations. Round your answer to 2 decimal places.) The series is % its average monthly level. c-3. Interpret the seasonal index for November. (Do not round intermediate calculations. Round your answer to 2 decimal places.) The series is % its average monthly level