A national nursing organization is lobbying congress for sunding to hire more nurses nationwide. One of the arguments is that nurses, on average, work significantly longer than full time duty,...

A national nursing organization is lobbying congress for sunding to hire more nurses nationwide. One of the arguments is that nurses, on average, work significantly longer than full time duty, assuming full time is 40 hours a week. A sample of n=9 nurses had the following work hours last week:

43, 45,48,41,45,50,50,53,48

Calculate the sample variance of work hours.