4. The risk-free rate is 3%, and the market risk premium rM rRF is 4%. Stock A has a beta of 1.2, and Stock B has a beta of 0.8. a. What is the required rate of return on each stock? b. Assume that investors become less willing to take on risk (i.e., they become more risk-averse), so the market risk premium rises from 4% to 6%. Assume that the risk-free rate remains constant. What effect will this have on the required rates of return on the two stocks? (PLEASE EXPLAIN IN DETAIL, THANK YOU)