When Did the Most Recent Ice Ages Occur

question 69

Multiple Choice

When did the most recent ice ages occur?

• A)the Jurassic period
• B)the Pleistocene epoch
• C)the Paleozoic era
• D)the Pliocene epoch

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Definitions:

Crown Height

The vertical distance between the top of a curved surface (like a road or a cam) and the chord (straight line) connecting the endpoints of the curve.

Whole Depth

In gear terminology, the total depth of a gear tooth space, from the top of the tooth to the bottom of the gullet.

Bevel Gears

Gears where the axes of the two shafts intersect and the tooth-bearing faces of the gears themselves are conically shaped.

Pitch Cone

In gear design, it is the imaginary cone that represents the underlying angular surface of the teeth, where the pitch surface of an infinitely small gear would be.