According to the Arguing History Video in Section 1

question 40

Multiple Choice

According to the Arguing History video in section 1.6,estimates of the number of people who lived in the Americas before the European arrival fall between

• A) 100,000 and 500,000
• B) 1 million and 5 million
• C) 10 million and 100 million
• D) 800 million and 1 billion

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Definitions:

Sphincter Pupillae

A ring of smooth muscle fibers around the edge of the pupil in the eye, which constricts the pupil in bright light.

Canal of Schlemm

A circular channel in the eye that collects aqueous humor from the anterior chamber and delivers it into the bloodstream.

Aqueous Humor

A clear fluid found in the eye, between the cornea and the lens, that helps maintain pressure and nourishes the cornea and lens.

Depth of Focus

The range within which an image can be moved away from or closer to a lens without significantly affecting its sharpness.