PDF chapter test TRY NOW

1. We spend more trying to find new ways of preventing fires.
Answer:
 
2. We generally do it with a lighted match.
Answer:
 
3. Oxygen comes from the air.
Answer:
 
4. The oxygen in the air combines with carbon and hydrogen in a fuel.
Answer: 
 
Important!
Note: If there are two answers in the same sentence, separate it by a semicolon (;) and write it in the answer box.