Why Is Secondary Treatment Often Needed for Sewage

question 62

Multiple Choice

Why is secondary treatment often needed for sewage?

• A)The dissolved organics are too high and lead to bacterial growth.
• B)The solution is contaminated with dangerous bacteria.
• C)There are too many dissolved inorganic compounds.
• D)There are too many finely divided particles that need to be filtered.
• E)none of the above

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Definitions:

Average Accounting Return

A measure of an investment's profitability, calculated as the average net income divided by the average investment.

Average Book Value

The mean value of an asset or investment determined by its original cost minus depreciation or amortization.

Average Cash Inflow

The mean amount of money received by a company over a defined period, typically calculated for assessment or planning purposes.

Average Net Income

The mean amount of revenue remaining after all expenses, taxes, and costs have been deducted over a certain period.