Suppose that a team of doctors is planning a study to test the effects of pain-relieving medications and exercise on arthritis. The two dosages of pain-relieving medications are 500 mg and 0 mg (placebo). The three levels of exercise are 20 minutes of exercise five days a week, 20 minutes of exercise three days a week, and 0 minutes of exercise. A random sample of 150 adults with arthritis were selected at random, and 25 were assigned to each of the six combinations of pain-relieving medications and exercise.
Which of the following statements about this experiment are true?
The treatments are pain-relieving medications and exercise.
The subjects of the experiment are the 150 adults with arthritis.
The subjects of the experiment are the different means of treating arthritis.
The factors are pain-relieving medications and exercise.
The factors are the six combinations of the two dosages of pain-relieving medications and the three levels of exercise.
The treatments are the six combinations of the two dosages of pain-relieving medications and the three levels of
exercise.