You have estimated the following probability distribution of returns for two stocks: Stock N Stock O Probability Return Probability Return 0.20 8% 0.20 26% 0.30 4 0.30 12 0.30 0 0.30 0 0.20 -4 0.20 -4 a. Calculate the expected rate of return and standard deviation for each stock. b. If the correlation between the returns on the two stocks is -0.40, calculate the portfolio return and the standard deviation for portfolios containing 100%, 75%, 50%, 25% and 0% of security N, respectively. c. Plot the results from b). Which portfolios lie on the efficient frontier? d. If there is no risk-free asset, which portfolio would you prefer? Why? Would other individuals necessarily choose the same portfolio?

i need help with b please. can you calculate it using formulas and not excel. thank you