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 = 6, x1 = 115.1, s1 = 5.07, n2 = 6, x2 = 129.1, and s2 = 5.39. 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.)