'

(a) You are given the following information about the four distinct portfolios: Portfolio Expected Return Standard Deviation 4% 12% B 6% 12% 6% 15% D 10% 18% Determine which two of the four given portfolios are NOT efficient and explain why. (b) The shaded area below represents the set of attainable portfolios consisting of 3 or more risky assets: 0.20 0.15 0.101 0.15 0.20 0.25 0.30 Identify the efficient frontier and clearly mark it on the graph