Use the Following to Answer Questions

question 161

Multiple Choice

Use the following to answer questions :
Figure: City with Two Polluters
-Which statement describes a positive externality?

• A) Sam dug a pond,so he could go fishing,but the pond has contributed to an explosion of mosquitoes in your neighbourhood.
• B) Sam has dozens of cats,and they come into your yard to hunt the birds that come to your birdbath.
• C) Sam buys a dilapidated house,renovates it,and increases the property values of all the houses in the neighbourhood.
• D) Liquid waste from Sam's chicken farm flows into a neighbour's well water.

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Definitions:

Walter Cannon

An American physiologist known for his work on the fight or flight response and for coining the term "homeostasis."

Stomach Contractions

The involuntary movements of the stomach muscles that mix and propel contents through the digestive system.

Ghrelin

A hormone produced mainly by the stomach that stimulates appetite and signals hunger to the brain.

Ghrelin

A hormone produced in the stomach that stimulates appetite, promoting the feeling of hunger before meals.