Problem 6-11 Consider historical data showing that the average annual rate of return on the S&P 500 portfolio over the past 85 years has averaged roughly 8% more than the Treasury bill return and that the S&P 500 standard deviation has been about 25% per year. Assume these values are representative of investors' expectations for future performance and that the current T-bill rate is 4%. Calculate the utility levels of each portfolio for an investor with A = 2. Assume the utility function is U= E(0) - 0.5 ~ Ao2. (Do not round intermediate calculations. Round your answers to 4 decimal places.) WBills WIndex U(A = 2) 0.0 1.0 0.8 0.2 04 0.6 0.6 0.4 0.8 0.2 1.0 0.0