Scenario: A thirteen-year-old girl and her grandfather walk into a caf together. They each drink a large coffee. Thirty minutes later, the girl feels jittery and her hands are shaking. Her grandfather feels fine. They both consumed the same amount, or had the same exposure, of caffeine, but their responses were quite different. Apparently, one received a larger dose of caffeine than the other.

Consider these facts. The girl weighs 36 kg (79 pounds) and her grandfather weighs 120 kg (264 pounds). A large coffee contains 360 mg of caffeine.

1. Who were the two individuals? 2. What chemical were they exposed to? 3. What was the effect on each individualharmful, beneficial, or neither? 4. How did you calculate their respective doses? 5. What were their respective doses?