By one week after conception, the multiplying cells have divided into outer cells enclosing a mass of inner cells. The inner cells will become the

Approximately what percent of American eighth-graders report using inhalants to get high?

A) 1 B) 4 C) 9 D) 13

Diagnosis of ADHD requires _______ or more of the nine symptoms for inattention and/or hyperactivity

a. three b. four c. six d. nine