An interdisciplinary research team has examined 35 U.S. cities, reviewing and grading each according to the following performance areas: financial management, capital projects, personnel policies, information technology, and managing for results. a The grades awarded were letter grades such as students might receive in school. We have rounded off the "+" and "-" portions of the letter grades so that they are simply A, B, C, D, or F, and the data are coded so that A = 4, B = 3, C = 2, D = 1, and F = 0. We have also included one more variable for each city: its population according to the latest census statistics at the time.b The data for all 35 cities are in file XR02053.

a. Construct a simple tabulation in which the counts are according to the grade on financial management.

b. Construct a cross-tabulation describing the cities, using grade on financial management and grade on information technology as the categorization variables.

c. Construct a display showing the average population size according to grade on financial management and grade on information technology. Do the categorization variables seem to be related to the level of population? If so, how?