[*Exercises 8.11, 8.20] n EX EX2 Commodity Sector 10 31.0 103.3 Value-Added Sector 47.7 262.5 a) Assume that you are in the commodity sector. Is it worth venturing into the value-added sector (ie, is it more profitable)? Use a hypothesis test at a 5% level of significance to draw your conclusions and make sure to test all of your assumptions. b) Find the 99% confidence interval for the variance of profit in the value-added sector. c) Find the 95% confidence interval for the ratio of variances for both sectors