The general social survey described in exercise 5.8 included random samples from two groups: us residents with a college degree and us residents without a college degree. for the 505 sampled us residents with a college degree, the average number of hours worked each week was 41.8 hours with a standard deviation of 15.1 hours. for those 667 without a degree, the mean was 39.4 hours with a standard deviation of 15.1 hours. conduct a hypothesis test to check for a difference in the average number of hours worked for the two groups