4. Consider the following returns for two investments, A and B, over the past four years: Investment A 2% 8% -4% 6% Investment B 6% 12% -8% 10% a. Which investment provides the higher return? Explain. b. Which investment provides less risk? Explain. c. Given a risk-free rate of 1.2%, calculate the sharp ratio for each investment. Which investment has performed better? Explain. d. Using coefficient of variation explain which investment is preferred to invest and why? 5. A sample of salaries of business graduates in a city revealed a mean income of $72,000 with a standard deviation of $3,000. a. Using Chebyshev's theorem, what percentage of the business graduates in this city earns at least $66,000 but no more than $78,000? b. Using Chebyshev's theorem, what percentage of the business graduates in this city earns at least $63,000 but no more than $81,000