Consider a random sample of 100 households from a middle-class neighborhood that was the recent focus of an economic development study conducted by the local government. Specifically, for each of the 100 households, information was gathered on each of the following variables: family size, location of the household within the neighborhood, an indication of whether those surveyed owned or rented their home, gross annual income of the first household wage earner, gross annual income of the second household wage earner (if applicable), monthly home mortgage or rent payment, average monthly expenditure on utilities, and the total indebtedness (excluding the value of a home mortgage) of the household. The data are in the file P9_26.XLS. 

Test for the existence of a significant difference between the mean indebtedness levels of the households in the first (i.e., SW) and second (i.e., NW) sectors of this community. Perform similar hypothesis tests for the differences between the mean indebtedness levels of households from all other pairs of locations (i.e., first and third, first and fourth, second and third, second and fourth, and third and fourth). Summarize your findings.