Chapter 2 - Science as a Way of Knowing: Critical Thinking about the Environment - Study Questions - Page 41: 6

(a) Independent variable: exercise Dependent variable: rate of breathing (b) Independent variable: study time Dependent variable: grades (c) Independent variable: exposure to smoke from other people's cigarettes Dependent variable: likelihood of contracting lung cancer

(a) The independent variable is the variable that is being manipulated or changed by the researcher in the experiment, which in this case is exercise. The dependent variable is the variable that is being measured in response to the change in the independent variable, which in this case is the rate of breathing. (b) The independent variable is the variable that is being manipulated or changed by the researcher in the experiment, which in this case is study time. The dependent variable is the variable that is being measured in response to the change in the independent variable, which in this case is grades. (c) The independent variable is the variable that is being measured or observed by the researcher in the experiment, which in this case is exposure to smoke from other people's cigarettes. The dependent variable is the variable that is being measured or observed as a result of the independent variable, which in this case is the likelihood of contracting lung cancer.