Niagara Falls Were Formed________

question 58

Multiple Choice

Niagara Falls were formed________ .

• A) after a series of spectacular earthquakes which are still helping the falls evolve
• B) after the retreat of the Pleistocene ice sheets a few thousand years ago
• C) so long ago that the river's knickpoint is now gone
• D) by humans as a result of the damming of the St. Lawrence River
• E) during Precambrian time approximately a billion years ago

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Definitions:

CA

A term often used to abbreviate cancer or carcinoma, indicating a variety of diseases characterized by the uncontrolled division of abnormal cells.

Meaning

The significance or understanding conveyed by a word, phrase, sentence, or text.

Lymphangiosarcoma

A rare and aggressive form of cancer that develops from the lymphatic system, often associated with chronic lymphedema.

Combining Form

A linguistic element used in the construction of medical and scientific terminology that generally consists of a root and a vowel to ease pronunciation when combined with another form.