Researchers Who Taught a Gorilla Named Koko to Use Sign

question 16

Multiple Choice

Researchers who taught a gorilla named Koko to use sign language found that by age 5, she had a vocabulary of about ________ words.

• A) 100
• B) 500
• C) 1,000
• D) 5,000

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Definitions:

Day

A unit of time equal to 24 hours, representing one complete rotation of the Earth on its axis.

Marginal Utility

The added satisfaction or utility gained from consuming an additional unit of a good or service.

Spending

Engaging in transactions to acquire goods or services by spending money.

Income

Earnings accrued from work or investment sources on a consistent basis.