Dr. cooke wanted to know if a drug was more effective than a placebo. she gave one group the real drug and measured its effectiveness, and gave the other group the placebo and measured its effectiveness. dr. cooke is doing a(n):

Urban growth invariably feeds increased commercialization and industrialization. it requires continually expanding land areas. when urbanization rates are high, and countries do not have the institutional and managerial capacities or economic wherewithal to manage such rapid growths, they exert intense pressure on the types and nature of the resulting settlements. they contribute to the development of overcrowded slums and shanty towns without adequate essential services and necessary infrastructure.-by asit k. biswas and cecilia tortajada