Please show all equations and work where necessary.

3. Elias is a risk-averse investor. David is a less risk-averse investor than Elias. Therefore, A. for the same risk, David requires a higher rate of return than Elias. B. for the same return, Elias tolerates higher risk than David. C. for the same risk, Elias requires a lower rate of return than David. D. for the same return, David tolerates higher risk than Elias. E. Cannot be determined. 4. According to the mean-variance criterion, which of the statements below is correct? E(r) 10% 21% 18% 24% Deviation 5% 11% 23% 16% Investment A. Investment B dominates investment A B. Investment B dominates investment C C. Investment D dominates all of the other investments. D. Investment D dominates only investment B. E. Investment C dominates investment A