Two catalysts in a batch chemical process are being compared for their effect on the output of the process reaction. A sample of 14 batches was prepared using catalyst 1 and gave an average yield of 88 with a sample standard deviation of 6. A sample of 11 batches was prepared using catalyst 2 and gave an average yield of 84 and a sample standard deviation of 4. Find a 95% confidence interval for the difference between the population means, assuming that the populations are approximately normally distributed with equal variances. Click here to view page 1 of the table of critical values of the t-distribution. Click here to view page 2 of the table of critical values of the t-distribution. Let , be the population mean for catalyst 1 and let be the population mean for catalyst 2. The confidence interval is