1. What harmful materials are created by human activity or by natural phenomenon?
A. ozone
B. pollution
C. acid rain
D. global warming
2. Which describe the chemical change cause by heat?
A. reversible
B. irresistible
C. irreversible
D. resistible
3. What materials contain a substance that cannot be broken down or decayed?
A. non-biodegradable
B. biodegradable
C. paper
D. chemical
4. What gas is used by animals and plants in their respiration (breathing process?
A. oxygen
B. carbon
C. nitrogen
D. helium
5. What is form of energy that can be transferred from one object to another
A. heat
B. thermometer
C. barometer
D. temperature