In a filtration, plant water is filtered using layers of (a) sand and clay. (b) clay and fine gravel. (c) sand and fine gravel. (d) sand, fine gravel and medium gravel.
ScienceClass 7CBSEAnswered 27 Mar 2026
Answer
Soln:
The answer is (d) sand, fine gravel and medium gravel.
Explanation:
During wastewater treatment wastewater is allowed to enter a grit of sand, fine gravel and medium gravel. Here the speed of wastewater is slowed down to allow sand, fine gravel and medium gravel to settle down.
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