Question 8. Recall that the single index model was a single factor model, and we needed to estimate 3N + 2 parameters from the data to construct an optimal portfolio with N assets. Suppose now you want to estimate the optimal portfolio in a two factor model. How many parameters would you need to estimate? O 3N +3 4N + 4 O5N + 5 O 6N + 6 Question 5. Suppose there are many risky assets and NO risk-free asset available to invest in. Suppose all agents are risk-averse mean-variance optimizers, but have different levels of risk aversion. Then they will invest in The same risky portfolio Different risky portfolios, but only risky portfolios on the efficient frontier Different risky portfolios, including portfolios not on the efficient frontier The minimum variance risky portfolio