4 Suppose we observe the 3-year Treasury security rate (1R3) to be 7 percent, the expected 1-year rate next yearE (2/1)to be 4 percent, and the expected 1-year rate the following yearE (3r1) to be 6 percent. If the unbiased expectations theory of the term structure of interest rates holds, what is the 1-year Treasury security rate, 1R1? (Round your answer to 2 decimal places.) Treasury security rate %