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Question 5 . Salaries for 20 male and 17 female school superintendents in a certain metropolitan are shown below. It is known that the standard deviation of the salaries are 10100$ and 12000$ for men and women, respectively. Men Women 114000 121421 94675 96000 115024 112187 123484 112455 115598 110160 99703 120118 108400 128322 86000 124163 109900 128041 108000 76340 120352 125462 94940 89600 118000 113611 83933 91993 108209 123814 102181 110000 111280 86840 151008 112280 85000 a) Estimate the difference between the salaries of men and women. b) level. Estimate the difference between the salaries of men and women with 95% confidence c) Do male and female school superintendents earn the same pay? Use o.01 significance level.Question 6 Concerned about graffiti, mayors of nine suburban communities instituted a citizen Community Watch program. Here are results. Community Monthly Incidents Before Monthly Incidents After Burr Oak Elgin Corners Elm Grove Greenburg Huntley North Lyman South Lyman Pin Oak Victorville WWAANH DONE a) Estimate the mean incidents between before and after the watch program. b) Estimate the mean incidents between before and after the watch program with 95% confidence. c) Are the number of graffiti incidents declined? Use 0.05 significance level