A portfolio manager summarizes the input from the macro and micro forecasters in the following table:

Micro Forecasts
Asset	Expected Return (%)			Beta	Residual Standard Deviation (%)
Stock A		23		1.8		57
Stock B		20		2.0		71
Stock C		19		1.1		62
Stock D		15		1.3		51

Macro Forecasts
Asset	Expected Return (%)			Standard Deviation (%)
T-bills		12			0
Passive equity portfolio		18			30

a. Calculate expected excess returns, alpha values, and residual variances for these stocks. (Negative values should be indicated by a minus sign. Do not round intermediate calculations. Round "Alpha values" to 1 decimal place.)

b. Compute the proportion in the optimal risky portfolio. (Do not round intermediate calculations. Enter your answer as decimals rounded to 4 places.)

c. What is the Sharpe ratio for the optimal portfolio? (Do not round intermediate calculations. Enter your answers as decimals rounded to 4 places.)

d. By how much did the position in the active portfolio improve the Sharpe ratio compared to a purely passive index strategy? (Do not round intermediate calculations. Enter your answers as decimals rounded to 4 places.)

e. What should be the exact makeup of the complete portfolio (including the risk-free asset) for an investor with a coefficient of risk aversion of 2.1?