Stocks X, Y, Z are currently traded at Px = $10, Py = $20, and Pz = $30. Their standard deviations of the returns are 0x = 8%, ay = 20%, and on = 14%. The return correlations between: (1) X and Y is 0.6, [2] X and Z is -0.2, and 3] Y and Z is 0.5. a. [1pt) What is the standard deviation of the returns of the equal-weighted portfolio of Stock X and Y? b. [1pt] What is the standard deviation of the returns of the price-weighted portfolio of Stock X and Z