What Do We Mean by a Mass Extinction

question 41

Multiple Choice

What do we mean by a mass extinction?

• A) The extinction of a large fraction of the world's plant and animal species in a relatively short period of time
• B) The extinction of large animals, such as dinosaurs
• C) An extinction caused by the impact of an asteroid or comet
• D) The extinction of any species of plant or animal that has mass

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Definitions:

Universal Joint

An assembly consisting of a trunnion cross and bearings that connects a pair of yokes for purposes of transmitting drive torque on an angled plane.

Trunnions

Trunnions are cylindrical protrusions used as a pivot or mounting point, commonly found in cannons, tanks, and heavy machinery for rotation or support.

Metal Fatigue

The phenomenon where metal experiences weakening or failure after repeated stress or strain over time.

U-joint Trunnion

Part of a universal joint that allows for the transfer of rotational movement in multiple directions, accommodating changes in angle between the parts it connects.