1. As a firefighter, explain why is it critical that we understand lower explosive limit and upper explosive limit? 2. If a gas has a vapor density of 1.8 how will it behave in the environment? What does this mean to a firefighter? 3. Explain specific gravity and how it affects response at hazardous material scenes. 4. Give me an example of how boiling point of material can affect decision making at an incident: 5. What surprised you most about the PH scale?