What is the 95% confidence interval for the difference in test scores at the two schools, assuming that test scores came from normal distributions in both schools?

What is the 95% confidence interval for the difference in test scores at the two schools, assuming that test scores came from normal distributions in both schools?

Suppose that simple random samples of college freshman are selected from two universities – 25 students from school A and 20 students from school B. On a standardized
test, the sample from school A has an average score of 990 with a standard deviation of 100. The sample from school B has an average score of 950 with a standard
deviation of 90. What is the 95% confidence interval for the difference in test scores at the two schools, assuming that test scores came from normal distributions in
both schools?