Consider the following table: Required: a. Calculate the values of mean return and variance for the stock fund. (Do not round intermediate calculations. Round "Mean return" value to 1 decimal place and "Variance" to 4 decimal places.) b. Calculate the value of the covariance between the stock and bond funds. (Negative value should be indicated by a minus sign. Do not round intermediate calculations. Round your answer to 4 decimal places.) x Answer is complete but not entirely correct. The standard deviation of the market-index portfolio is 20%. Stock A has a beta of 1.50 and a residual standard deviation of 30%. Required: a. Calculate the total variance for an increase of 0.15 in its beta. (Do not round intermediate calculations.) b. Calculate the total variance for an increase of 3% in its residual standard deviation. (Do not round intermediate calculations.)