Executives often spend so many hours in meetings that they have relatively little time to manage their individual areas of operation.What is the difference in mean time spent in meetings by executives of the aerospace industry and executives of the automobile industry? Suppose random samples of 33 aerospace executives and 35 automobile executives are monitored for a week to determine how much time they spend in meetings. The results follow.

Use the data to estimate the difference in the mean time per week executives in these two industries spend in meetings. Use a 99% level ofconfidence.

Aerospace Automobile n, = 35 x 12.4 hours = 2.9 hours = 4.6 hours -= 1.8 hours