A portfolio manager summarizes the input from the macro and micro forecasters in the following table Micro Forecasts Asset Stock A Stock B Stock C Stock D Expected Return(%) 25 19 16 13 Beta 1.2 1.6 0.5 1.0 Residual Standard Deviation(%) 56 70 61 53 Macro Forecasts Expected Standard Return(%) Deviation (%) Asset T-bills Passive equity portfolio 7 15 0 21 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.Omit the "%"' sign in your response.) Stock A Stock B Stock C Stock D Excess returns Alpha values Residual variances b. Compute the proportion of risky assets invested in the active portfolio. (Do not round intermediate calculations. Enter your answer as decimals rounded to 4 places.) Proportion