The Bottom or Downward Tip of a Crevasse Marks the _________

question 19

Multiple Choice

The bottom or downward tip of a crevasse marks the _________.

• A) boundary between parts of the glacier moving by basal sliding and crevassal slip
• B) boundary between the basal sliding and external flowage zones
• C) top of the internal deformation and flowage zone, and the base of the brittle zone of fracture
• D) bottom of the basal sliding zone

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Definitions:

Proximate Levels

Describes immediate, underlying causes of biological processes or behaviors, focusing on how they occur.

Ultimate Levels

Explanations in biology that address why events occur, based on evolutionary significance and history.

Sonograms

Visual representations of the spectrum of frequencies of sound as they vary with time, often used in bird song analysis.

Acoustic Stimulus

A sound or auditory signal that triggers a response in a receiver, commonly studied in animal communication and human psychology.