The standard deviation of the market-index portfolio is 25%. Stock A has a beta of 1.80 and a residual standard deviation of 35%. Required: a. Calculate the total variance for an increase of 0.20 in its beta. (Do not round intermediate calculations.) Answer is complete but not entirely correct. b. Calculate the total variance for an increase of 0.06 percentage points in its residual standard deviation. (Do not round intermediat calculations.) x Answer is complete but not entirely correct