Suppose μ1 and μ2 are true mean stopping distances at 50 mph for cars of a certain type equipped with two different types of braking systems. The data follows: n1 = 9, x1 = 115.8, s1 = 5.09, n2 = 9, x2 = 129.7, and s2 = 5.33. Calculate a 95% CI for the difference between true average stopping distances for cars equipped with system 1 and cars equipped with system 2. Use the conservative degrees of freedom, min(n1-1,n2-1) (Round your answers to two decimal places.)