Use the tdistribution to find a confidence interval for a difference in means 1 2 given the relevant sample results. Give the best estimate for 1 2, the margin of error, the relevant degrees of freedom, and the confidence interval. Assume the results come from random samples from populations that are approximately normally distributed. A 90% confidence interval for 1 2 using the sample results x1 = 10.1, s1 = 2.3, n1 = 50, and x2 = 12.4, s2 = 5.7, n2 = 50. Note that here t = 1.677.