Please find expected rate of return!

Suppose that many stocks are traded in the market and that it is possible to borrow at the risk-free rate, rf. The characteristics of two of the stocks are as follows: a. Calculate the expected rate of return on the risk-free portfolio? (Hint: Try to construct a risk-free portfolio using stocks A and B.) (Enter your answer as a percentage rounded to 2 decimal places.) b. Could the equilibrium f be greater than, equal to, or less than your answer in #a? greater than equal to less than