Dr. Johnson wants to test the effectiveness of a new experimental drug to decrease smoking. To test the effectiveness of the new drug, Dr. Johnson recruits smokers through a series of advertisements and assigns them to the experimental group. Dr. Johnson also forms a control group of non-smokers who are given a placebo. Before the experiment is completed several participants in the experimental group decide to leave the study. Even so, Dr. Johnson concludes that the new drug is effective when used to decrease smoking. I 1. What is the independent variable? 2. What is the dependent variable? 3. Create an operational definition for the dependent variable you identified. Your definition must be precise and allow for an appropriate measure of this variable. 4. What confound is present in this example? Explain the confound you have identified. 5. Does this study show a high degree of internal validity? Explain why or why not?