If the sampling distribution of 10 X1 - X2 cannot be assumed normal, we 8 00:36:27 Multiple Choice are still able to use the z distribution to compute a confidence interval must use the tof distribution and calculate the degrees of freedom using n1, n2, S1, and $2 to compute a confidence interval are unable to compute a confidence interval must use the tof distribution with n1 + n2 - 2 degrees of freedom to compute a confidence interval Mc