pollutants are produced due to ?
(a) birds activity .
(b) water activity .
(c) both a and b .
(d) none of these .
class 9 computer questions
Answers
Answer:
Air pollution is caused by solid and liquid particles and certain gases that are suspended in the air. These particles and gases can come from car and truck exhaust, factories, dust, pollen, mold spores, volcanoes and wildfires.
Answer:
12. Seed drill, because it is a modern agricultural implement unlike
the others which are all traditional tools.
13. The field will be watered, tilled and ploughed before sowing seeds.
14. (i) False: Apart from good quality seeds, using appropriate
agricultural practices are important for getting higher
yield.
(ii) False: It actually enriches the soil.
(iii) False: Some crop plants need transplantation.
(iv) False: Rhizobium (bacteria) present in the cells of root
nodules of leguminous, plants fix nitrogen.
(v) True.
15. October to March.
16. Loosening the soil/maintaining high moisture levels in soil.
Explanation: