Suppose that the index model for stocks A and B is estimated from excess returns with the following results: = RA 2.4% +0.85RM + A = RB -2.4% + 1.30RM + B OM = 25%; R-square = 0.17; R-squareg = 0.11 Assume you create a portfolio Q, with investment proportions of 0.50 in a risky portfolio P, 0.30 in the market index, and 0.20 in T-bill. Portfolio Pis composed of 60% Stock A and 40% Stock B. a. What is the standard deviation of portfolio Q? (Calculate using numbers in decimal form, not percentages. Do not round intermediate calculations. Round your answer to 2 decimal places.) Standard deviation 0.31 % b. What is the beta of portfolio Q? (Do not round intermediate calculations. Round your answer to 2 decimal places.) Portfolio beta 0.82