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Fortune Magazine (March 1997) reported the average returns to investors for the 10 years prior to 1996 and also for Fiscal Year 1996 for a sample of ten companies. The data is listed below 1986 to Firm 1995 Fiscal Year 1996 Coca-Cola 29.8% 43.3% Mirage Resorts 27.9% 25.4% Merck 22.1% 24.0% Microsoft 44.5% 88.3% Johnson & Johnson 22.2% 18.1% Intel 43.8% 32.2% Pfizer 21.7% 34.0% Procter and Gamble 21.9% 32.1% Berkshire Hathaway 28.3% 6.2% General Motors 11.8% 20.3% Question 1 (Note: please provide all the formula you use, including sample variance formula) a. Find a 90% confidence interval for the ratio of the variances between the two samples(1986 to 1995 the 10 years can be treated as one sample). (5 points) b. Using a confidence interval approach, determine if there is any evidence that these two variances are different. Please specify the reason why you think the variances are or are not different. (2 points) c. Find a 90% prediction interval for the fiscal year 1996. (5 points) (12 points)