How were African Americans affected by the postwar economy? All African Americans remained in their wartime jobs.
Most African Americans remained in rural areas.
Many African Americans moved to cities for jobs.
All African Americans enjoyed equal rights.

Martha participates in a research study in order to receive extra credit for her psychology class. when she arrives in the research office she is given a can of what looks and tastes like beer, but which actually contains no alcohol. in the adjoining room martha's classmate karen is also participating in the study. karen receives a can of alcoholic beer. if the experiment was designed to test the effects of alcohol on concentration, then who is exposed to the independent variable?