A national police organization is lobbying congress for funding to hire more police officers in cities nationwide. One of its arguments is that officers on average work significantly longer than full-time duty assuming full time is u=40 hours per week. A sample of n=9 officers from a medium-sized city had the following work hours last week: 43, 45, 48, 41, 45, 50, 50, 53, 48. Do these data support the claim of the national police group? Use a one-tailed test of alpha=.05.
The estimated standard error is equal to what?
Could someone please show me how this problem is worked out?