In Which Phase of Sewage Treatment Are Trickling Filters Sometimes

question 45

Multiple Choice

In which phase of sewage treatment are trickling filters sometimes used?

• A) Primary treatment.
• B) Secondary treatment.
• C) Tertiary treatment.
• D) Quaternary treatment.
• E) All of these.

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Inflation Rate

The rate at which the general level of prices for goods and services is rising, and, subsequently, purchasing power is falling, often expressed as a percentage.

Base Year

A reference year against which economic growth, price levels, and other data are measured over time.

Consumer Price Index

An economic indicator that measures the average change over time in the prices paid by consumers for a basket of goods and services.

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The total expense of a selected set of goods and services over a period, often used to measure inflation.