Please show all equations and work where necessary.

7. Based on their relative degrees of risk tolerance A. investors will hold varying amounts of the risky asset in their portfolios B. all investors will have the same portfolio asset allocations. C. investors will hold varying amounts of the risk-free asset in their portfolios. D. investors will hold varying amounts of the risky asset and varying amounts of the risk-free asset in their portfolios. 8. Consider a risky portfolio, A, with an expected rate of return of 0.15 and a standard deviation of 0.15, that lies on a given indifference curve for a risk-averse investor. Which one of the following portfolios might lie on the same indifference curve for a risk averse investor? A. E(r) 0.15; Standard deviation -0.20 B. E(r)-0.15; Standard deviation 0.10 C. E(r)-0.10; Standard deviation 0.10 D. E(r)-0.20; Standard deviation-0.15 E. E(r) 0.10, Standard deviation-0.20