Question

Which of the following might not be true?

• A. More amount of organic material in the sewage indicates lower biochemical oxygen demand.
• B. Domestic sewage can hamper the growth of algae in water and harm the aquatic plants.
• C. England was the first country to introduce sanitary landfills in the year 1912.
• D. Eucalyptus trees should be planted near sewages as their smell can keep the insects away.

Answer 1

Answer: (A), (B), (D)

The correct options are
A More amount of organic material in the sewage indicates lower biochemical oxygen demand.
B Domestic sewage can hamper the growth of algae in water and harm the aquatic plants.
D Eucalyptus trees should be planted near sewages as their smell can keep the insects away.

The amount of putrescible organic material in sewage is specified by the biochemical oxygen demand. More the amount of organic material more will be the biochemical oxygen demand.

Plants require phosphorous and nitrogen to grow. These are present in domestic sewages and can lead to excessive growth of algae.

Eucalyptus can absorb the excess water from the sewage and should be planted near it.