11. Using of eco bag when going for groceries is what kind of 5R's?
A. Reuse
B. Repair
C. Recycle
D. Reduce
12. Making of compost pit is what kind of 5R's?
A. Reuse
B. Rot
C. Recycle
D. Reduce
13. It is a useful change in materials to one's environment.
A. Burning of old tire.
C. Plastic bottle can used as flowerpots.
B. Throwing of garbage in the canal.
D. Cutting of trees.
14. It is a harmful change in materials to one's environment.
A. Cutting of fabric to be made into clothes. C. Plastic bottle can used as flowerpots.
B. Burning of garbage.
D. Old tire can used as chair or plant pots
15. How can harmful changes in materials affect one's environment?
A. It can cause land pollution.
C. It can cause air pollution.
B. It can cause water pollution.
D. All the choices.​