Sample variances were computed for the tidal volumes (milliliters) of two groups of patients suffering from atrial septal defect. The results and sample sizes were as follows:

n1 ¼ 31; s2 1 ¼ 35; 000 n2 ¼ 41; s2 2 ¼ 20; 000 Construct the 95 percent confidence interval for the ratio of the two population variances.