All questions are worth 20 points:

1. What determines if drug use will be defined as drug abuse?
2. When can the use of psychoactive chemicals be objectively labeled drug abuse?
3. How did the changes in the marijuana-using population lead to changes in policies, like the Marijuana Tax Act?
4. Throughout history, different drugs were introduced in the United States for purposes other than getting high, do you believe in the reasons behind this? Please give examples in your answer. Does the United States still practice this method; if so, what problems have arisen today because of this practice?
5. What is the role of dopamine in regards to the Central Nervous System? What are the three broad categories of substances that affect the Central Nervous System? Choose one of these categories and explain how it affects the Central Nervous System.