I can not figure out how to solve this problem

The Yo-Yo Corporation tries to determine the appropriate cost for retained earnings to be used in capital budgeting analysis. The firm's beta is 0.96. The rate on six-month T-bills is 3.69%, and the return on the S&P 500 index is 6.65%. What is the appropriate cost for retained earnings in determining the firm's cost of capital?

Round the answers to two decimal places in percentage form.