Brent, a pet supply store owner, is comparing the weights of two different breeds of dogs. A sample of 41 adult male Pembroke Welsh corgis had an average weight of 11.85 kilograms. A sample of 38 adult male border collies had an average weight of 17.11 kilograms. Assume that the population standard deviations for the weights of Pembroke Welsh corgis and border collies are 1.35 kilograms and 2.12 kilograms, respectively. Find the 90 % confidence interval for the difference in mean weights between Pembroke Welsh corgis and border collies. Let the Pembroke Welsh corgis be the first sample, and let the border collies be the second sample. Assume the samples are random and independent. Assume that both the population distributions are normally distributed. Round your answer to two decimal places. Confidence Level Corresponding z c Value 90 % confidence z c = 1.645 95 % confidence z c = 1.96 99 % confidence z c = 2.576