1. A researcher studies the effects of different diets on weight loss among college students. What is the independent variable? a. Age b. Weight loss c. Diets d. Exercise 2. What could a researcher do to control for design confounds? a. Counterbalance b. Use control variables C. Use within-groups designs d. Increase demand characteristics A researcher is studying the effect of caffeine on problem solving ability. A sample of 200 college students is selected. 100 students are given 10 oz of coffee. 100 students are given 20 oz of coffee. After 1 hour, all students complete a puzzle task, and the researcher records how quickly they solve the puzzle. The researcher compares scores from each group. In this example.. 3. What is the dependent variable? 4. What is the experimental design? 5. How many levels are there of the independent variable