Given variance-covariance matrix:

24 -10 9

10 75 3

9 3 12

(a) Calculate the variance of an equally weighted portfolio.

(b) Calculate the covariance of a portfolio that has 10% in asset 1, 80% in asset 2, and 10% in asset 3 with a second portfolio that has 125% in asset 1, -10% in asset 2, and -15% in asset 3.