Answer:
ER(P) = Rf + β(Rm - Rf)
11.75 = 4.30 + 1.23(Rm - Rf)
11.75 - 4.30 = 1.23Rm - 5.289
7.45 + 5.289 = 1.23Rm
12.739 = 1.23Rm
Rm = 12.739/1.23
Rm = 10.36%
Explanation: The expected return of a stock is a function of risk-free rate plus market risk premium. Market risk premium is equal to beta multiplied by risk premium. Risk premium is market return minus risk free rate.