28. Portfolio Standard Deviation Suppose the expected neture and an dard deviations of Stocks A and Bl are E(RA) = 10, E(R)) = 12, 0, 30 and 0. 72, a. Calculate the expected retum and standard deviation of a portfolo that is composed of 40 percent aid 60 percent B when the correlation between the returns on A and B is 6. b. Calculate the standard deviation of a portfolio with the same portfolio weights as in part ay when the correlation coefficient between the returns on A and B 3-5 c.How does the comslation between the retums an A and B affect the stadand deviation of the portfulo?

28. Portfolio Standard Deviation Suppase the expectad retirns and standard deviabons of Stocks A and B are E(RA)=10,E(RG)=12,A=39, and A=72 a. Calculato the expected retum and standard deviation of a portolio that is composed of 40 percent A and EO percent B when the correlation between the returns on A and B is .5 b. Calculate the standard deviation of a portfolio with the same porffolio weights as in part (i) when the correlation coeticient between the fetums on A and B is -5 . c. How does the correlation betwoen the refurns on A and B affect the standard duviation of the porfolid