How Old Are the Oldest Zircon Minerals on Earth

question 8

Multiple Choice

How old are the oldest zircon minerals on Earth?

• A)approximately 10,000 years old
• B)approximately 500 million years old
• C)approximately 65 million years old
• D)approximately 4 billion years old

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Definitions:

Unconditioned Stimulus

A stimulus that instinctively elicits a response without any prerequisite learning.

Conditioned Stimulus

A once-neutral trigger that, upon association with an unconditioned stimulus, in time provokes a conditioned response.

Extinction

In psychology, the gradual weakening and disappearance of a conditioned response when the conditioned stimulus is no longer paired with the unconditioned stimulus.

Discrimination

The unjust or prejudicial treatment of different categories of people, especially on the grounds of race, age, sex, or disability.