Use this information to answer questions 18 and 19: Portfolio has a standard deviation of 55% and the market has a standard deviation of 40%. Assume that the correlation coefficient between Portfolio A and the market is 0.50. 18. What is the percentage of the total return of portfolio A is unsystematic risk? a. 25% b. 50% c. 75% d. 100% 19. What portfolio measures is best used to evaluate the performance of portfolio A? a. Sharpe ratio b. Jensens alpha c. Treynor ratio d. Information ratio