Biological and environmental influences that are similar for individuals in a particular age group, regardless of where they are raised, are what type of influences?

Most people would agree that anxiety can lead to sleep loss. However, Dr. Jenkins believes that sleep deprivation can also cause increased anxiety. Which research method would allow him to test a cause-effect relationship between the two?

a. Naturalistic observation b. Experimental c. Correlational d. Survey

REM is the sleep stage when:

a. The person's muscles are most active b. Dreams usually occur c. Most brain activity decreases d. A person is beginning to wake