Of the World's 177 Longest Rivers,only ____________________ of Them Run

question 51

Short Answer

Of the world's 177 longest rivers,only ____________________ of them run freely all the way to the sea.

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Definitions:

Chemical

A substance with a distinct molecular composition that is produced by or used in a chemical process.

Absolute Sensory Threshold

The minimum intensity of a stimulus that one can perceive, marking the boundary between detectable and undetectable levels of sensory input.

Stimulus

A change in the environment that influences or causes a response in an organism.

Minimum Intensity

The lowest level of stimulus intensity that is necessary to produce a perceptible sensation or response in the observer.