Problem 4 A late penalty of 35% will apply to new answers. Intro An investor holds two well-diversified portfolios on US securities. The expected return on portfolio A is 12% and the expected return on portfolio B is 8%. The investor identified that the US economy has only one factor (industrial production), and BA = 1 and BB = 0.7. Attempt 1/10 for 6.5 pts. Part 1 What should be the risk-free rate according to the APT? A+ decimals Submit