Which one of the following statements is most accurate for law enforcement?

a. the recruitment and training of police officers is handled by the department of homeland security.
b. law enforcement officers are required to uphold the law.
c. law enforcement agencies are employed by the court system.
d. ordinary police officers aren't required to understand how to gather evidence.

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?