Which of the Following Methods Use Microbial Biofilms for Secondary

question 26

Multiple Choice

Which of the following methods use microbial biofilms for secondary phase of wastewater treatment?

• A)trickling filter
• B)activated sludge
• C)anaerobic digester
• D)nitrification tank
• E)oxidation pond

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Definitions:

Sand

Coarse particles of rock and mineral, typically smaller than gravel and larger than silt, often found on beaches, deserts, and riverbeds.

Deep-Sea Floor

The bottom of the ocean at great depths, characterized by cold temperatures, high pressure, and darkness.

Fine Dust

Extremely small solid particles suspended in the air or settled on surfaces, often resulting from industrial activities or natural processes.

Single-Celled Organisms

Organisms consisting of a single cell, carrying out all life processes within it; examples include bacteria and certain algae.