Severe recession 0.05 –31 % –10 % mild recession 0.25 –11 % 16 % normal growth 0.40 16 % 9 % boom 0.30 21 % –6 % 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 2 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 2 decimal places.)