Decide Whether or Not the Set Is Closed Under Addition $$\{ \mathrm { n } \in \mathrm { N } : \mathrm { n } \geq 53 \}$$

question 172

Multiple Choice

Decide whether or not the set is closed under addition.
- $$\{ \mathrm { n } \in \mathrm { N } : \mathrm { n } \geq 53 \}$$

• A) Closed
• B) Not closed

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Definitions:

Nitrification

A microbiological process where ammonia is oxidized to nitrite and then to nitrate, which is a key step in the nitrogen cycle in ecosystems.

Carbon Cycle

The series of processes by which carbon compounds are interconverted in the environment, incorporating the absorption of carbon dioxide by plants and its release back into the atmosphere through respiration, the burning of fossil fuels, and other activities.

Aerobic Respiration

A process of producing cellular energy involving oxygen.

Aquatic Systems

Environments composed of water, including oceans, lakes, rivers, and wetlands, supporting diverse life forms.