Question

q.5. which of the following greenhouse gases are synthetic, does not occur naturally?
a) methane
b) carbon dioxide
c) chlorofluorocarbons (cfcs)
d) water vapor

q.6. which of the following activities do not increase the net carbon dioxide (co₂) in the atmosphere?
a) burning fossil fuels
b) deforestation
c) volcanic activity
d) photosynthesis

q.7. which of the following greenhouse gas is generated by livestock farming and the decomposition of solid waste in landfills?
a) water vapor (h₂o)
b) carbon dioxide (co₂)
c) nitrous oxide (n₂o)
d) methane (ch₄)

q.8. the surface of earth would be __________ without natural greenhouse gasses.
a) warmer
b) colder
c) same

q.9. which of the following greenhouse gases are mainly released from aerosols (such as hairspray cans), air conditioners, refrigeration, and in making foam plastics?
a) methane
b) carbon dioxide
c) chlorofluorocarbons (cfcs)
d) water vapor

Explanation:

Q.5:

Methane, carbon dioxide and water vapor occur naturally. CFCs are man - made.

Q.6:

Burning fossil fuels, deforestation and volcanic activity release CO₂. Photosynthesis absorbs CO₂.

Q.7:

Methane is produced by livestock farming and solid - waste decomposition in landfills.

Q.8:

Natural greenhouse gases trap heat. Without them, Earth would be colder.

Q.9:

CFCs are released from aerosols, air - conditioners, refrigeration and in making foam plastics.

Answer:

Q.5. C. Chlorofluorocarbons (CFCs)
Q.6. D. Photosynthesis
Q.7. D. Methane (CH₄)
Q.8. B. colder
Q.9. C. Chlorofluorocarbons (CFCs)