You have just begun studying unemployment rates in a city with fifty million people, of which fifteen million are unemployed. If you are using your sociological imagination, what is your first consideration

Chen's research team randomly assigned some newborns and their mothers either to a breastfeeding promotion group (where breastfeeding was encouraged, but not required) or to a normal pediatric care group (where breastfeeding was neither encouraged nor discouraged). which research method did they use?