Suppose that the current one-year rate and expected one-year T-bill rates over the following three years (ie.. years 2, 3, and 4, respectively) are as follows: IRI - 2.184, E21) 3.87%E(3r) -5.7%, E(41) - 7.8% Using the unbiased expectations theory, calculate the current (long-term) rates for four-year-maturity Treasury securities Write your awer in percentage and round it to 2 decimal places)