Q: What is the most significant cause of respiratory disease as well as cardiovascular disease and cancer? Choices: - sleeping - running - driving - smoking A:
smoking

Q: What is the name for a substance that can be used to follow the pathway of that substance through some structure? Choices: - gel - tracker - solution - tracer A:
tracer

Q: How many chambers does the stomach of a crocodile have? Choices: - six - ten - three - two A:
two