what is the real risk free rate return? help pls

Suppose 1-year T-bills currently yield 7.00% and the future inflation rate is expected to be constant at 2.00% per year. What is the real risk-free rate of return, r*? The cross-product term should be considered, i.e., if averaging is required, use the geometri average. (Round your final answer to 2 decimal places.) a. 6.86% b. 5.00% c. 9.14% d. 4.50% e. 4.90%