A psychologist expects physical activity to be related to performance on a measure of creativity. She randomly assigns participants to walk or run on a treadmill for 10 minutes before she measures their creativity. Which of the following best describes the hypothesis in this study?

The term psychologists use to describe how close two people live to each other is ______

a. propinquity c. proximity b. reciprocity d. complementarity

On average, most infants will use their first word ____

a. a few months before or after their second birthday b. a few months before or after their first birthday c. toward the middle half of their first year d. toward the second half of their second year