A portfolio has an expected rate of return of 0.12 and a standard deviation of 0.12. the risk-free rate is 6 percent. An investor has the following utility function U=E(r)-(A/2)S^2 Which value of A makes this investor indifferent between the risky portfolio and the risk-free asset? 5 or 4 or 3 or7 or 6 or 8 or 1