Answer:
Alpha for A is 1.40%; Alpha for B is -0.2%.
Explanation:
First, we use the CAPM to calculate the required returns of the two portfolios A and B given the risks of the two portfolios( beta), the risk-free return rate ( T-bill rate) and the Market return rate (S&P 500) are given.
Required Return for A: Risk-free return rate + Beta for A x ( Market return rate - Risk-free return rate) = 5% + 0.7 x (13% - 5%) = 10.6%;
Required Return for A: Risk-free return rate + Beta for B x ( Market return rate - Risk-free return rate) = 5% + 1.4 x (13% - 5%) = 16.2%;
Second, we compute the alphas for the two portfolios:
Portfolio A: Expected return of A - Required return of A = 12% - 10.6% = 1.4%;
Portfolio B: Expected return of B - Required return of B = 16% - 16.2% = -0.2%.