In the United States today, the average __________ is 78.5 years—nearly 76 for men and 81 for women

Primary aging is the inevitable biological aging that takes place in all members of the human species, as it takes place in all living organisms

a. true b. false

Several of her friends suspect that Marnie is using some sort of drug. She is very thin, stays awake for long periods of time, and is often jittery, nervous and somewhat paranoid. If Marnie is using a drug, it is likely to be _____.

Fill in the blank(s) with the appropriate word(s).