Consider the following statements: 1.Hallucinogen includes a wide variety of chemicals that cause metabolic stimulation and mood elevation. 2.Some stimulants are synthetic, and others are derived from certain plants. 3.Tranquilizers, valium, librium, reserpines are common mood elevators. 4.Depressants depress the action of the central nervous system – some relieve pain, other relieve anxiety and relax muscles and yet other increase drowsiness and sleep. Which of the above statements are incorrect?