Security and Investment Analysis (Finance II)

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Assume both portfolios A and Bare well diversified, that E(r_A) = l4% and E(r_B) = l4.8%. If the economy has only one factor, and beta for A 1 while beta for B - 1.1, what must be the risk-free rate? If simple CAPM is valid, which of situations are possible and why: Given the following data on bond yields, is the confidence index rising or falling? What might explain the pattern of yield changes? What is Efficient Market Hypothesis