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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) 0.25; (iii) 0.50; (iv) 0.75; (v) 1.0? (Leave no cells blank - be certain to enter "O" wherever required. Do not round Intermediate calculations. Enter the value of Expected return as a percentage rounded to 2 decimal places and value of Beta rounded to 2 decimal places.) Beta Expected Retum 12.00% 0 (0) (ii) 0.25 % 0.50 % (ii) (iv) 0.75 % [(v) 1.0 % b. How does expected return vary with beta? (Do not round intermediate calculations.) by The expected return % for a one unit increase in beta