stock of Firm A and Firm B:

a$.$ If Mary invests half her money in each of the two common stocks, what is the portfolio's expected rate of return and standard deviation in portfolio return?

b$.$ Answer part a where the correlation between the two common stock investments is equal to zero.

c$.$ Answer part a where the correlation between the two common stock investments is equal to $+1.$

d$.$ Answer part a where the correlation between the two common stock investments is equal to $-1.$

e$.$ Using your responses to questions $a-d,$ describe the relationship between the correlation and the risk and return of the portfolio.