Air

• A

• B

• C

• D

Which gases are present in the atmosphere of the planet in a higher percentage than they are in the Earth’s atmosphere?

• carbon dioxide and oxygen

• carbon dioxide only

• nitrogen and oxygen

• nitrogen only

• A

• B

• C

• D

• A

• B

• C

• D

For which of the following thing, where liquid nitrogen is not used

• Freeze food in factories

• Freeze liquid in cracked pipes

• For combustiion

• A

• B

• C

• D

• A

• B

• C

• D

• A

• B

• C

• D

• A

• B

• C

• D

Which of the following is the correct word equation for photosynthesis?

• glucose → carbon dioxide + ethanol

• glucose + oxygen → carbon dioxide + water

• carbon dioxide + water → glucose + oxygen