18. Materials made of paper are harmless but they become sources of
carbon dioxide when burned. How will you dispose of your used paper?
A. Burn it.
B. Put it inside your bag and use for cooking
c. Put it in the box for recycling.
D. Throw it outside the room.
19. Which of the following changes in the materials are harmful to the
environment?
A. Dumping of the garbage along the streets.
B. Throwing garbage properly.
C. Using paper bags when going to the market.
D. Reusing plastic containers.
20.When soil is polluted, which could be the result?
A. Growing of plants is not possible.
B. Plants get healthier.
C. Soil is rich in nutrients.
D. Water is safe for drinking.