Understanding CAPM and beta. Assume the common stock of Starbucks has a beta of β = 1.5 and a standard deviation of σ = 15.5 percent. Also assume the rate of return on the market is Rm = 12.5 percent and the risk-free rate of return is Rf = 5 percent. According to CAPM, what is the expected return E(Ri) on the common stock of Starbuck's?