The supreme court established that government aid to religious schools would be accepted as constitutional if it had a secular purpose, its effect was to neither advance nor inhibit religion, and it did not entangle government and religious institutions in each other’s affairs. this became known as the test.

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?