Historically,N₂ Only Entered the Atmosphere as a Result of Nitrogen

question 38

Multiple Choice

Historically,N₂ only entered the atmosphere as a result of nitrogen fixation by bacteria and archaea.How has human technology affected nitrogen cycling?

• A) Humans genetically modified plants to allow them to fix nitrogen.
• B) Humans developed a method for artificially fixing nitrogen to generate fertilizers.
• C) Humans use nitrogen as a source of renewable energy.
• D) Human technology has had no effect on nitrogen cycling.

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Definitions:

Direct Labor-Hours

The total hours of labor work directly on manufacturing a product or providing a service, often used in costing and pricing decisions.

Milling Department

A section within a manufacturing facility where the process of grinding, cutting, pressing, or crushing materials occurs.

Overhead Applied

The portion of manufacturing overhead costs allocated to each unit of production based on a predetermined rate or method.

Machine-Hours

A measure of production activity that represents the hours machines are operating to manufacture products.