What materials contain a substance that cannot be broken down or decay? *
a. non-biodegradable
b. biodegradable
c. paper
d. chemical

What gas is used by animals and plants in their respiration (breathing) process? *
a. oxygen
b. carbon
c. nitrogen
d. helium


What form of energy can be transferred by one object to another? *
a. heat
b. thermometer
c. barometer
d. thermometer