Problem 12-15 Portfolio Risk and Return (LO2) Suppose that the S&P 500, with a beta of 1.0, has an expected return of 12% and T-bills provide a risk-free return of 3%. a. What would be the expected return and beta of portfolios constructed from these two assets with weights in the S&P 500 of (0) 0: (1) .25; (111) .50; (iv) .75; (6) 1.0? (Leave no cells blank - be certain to enter "0" wherever required. Do not round intermediate calculations. Round your answers to 2 decimal places.) Beta Expected return 1% 1 (0) 0 (ii) 25 (ili) .50 (iv) .75 (v) 1.0 de dede de b. How does expected return vary with beta? (Do not round intermediate calculations.) The expected return increases beta. by % for a one unit increase in