Question
The diagram shows a sewage treatment process.
What is structure X?
(A) aeration tank
(B) anaerobic tank
(C) settlement tank
(D) storage tank
▶️Answer/Explanation
Ans: A
Question
Which two gases enhance the greenhouse effect?
A carbon dioxide and methane
B carbon dioxide and nitrogen
C methane and oxygen
D nitrogen and oxygen
▶️Answer/Explanation
Ans A
Question
The increase of which gases contributes to an enhanced greenhouse effect?
A carbon dioxide and methane
B methane and nitrogen
C nitrogen and oxygen
D oxygen and carbon dioxide
▶️Answer/Explanation
Ans A
Question
What are the effects of sewage pollution on the biodiversity and the number of bacteria in a river?
▶️Answer/Explanation
Ans B