The Standard Unit of Time, the Second, Is Now Defined

question 79

Multiple Choice

The standard unit of time, the second, is now defined with reference to

• A) the Earth's revolution period.
• B) the mean solar day.
• C) the cesium-133 atom.
• D) the Earth's rotation period.

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Definitions:

Coliform Bacteria

A group of bacteria predominantly found in the intestines of warm-blooded organisms and in their waste, used as an indicator of sanitary quality of water and food.

Indicator

A variable or criterion that serves to measure or demonstrate the state or level of something, often used in environmental, economic, and social contexts.

Organic Wastes

Biological materials originating from living organisms that are capable of being decomposed by other living organisms.