$Q _ { d } = 100 - 5 P + 0.004 M - 5 P _ { R }$

question 18

Multiple Choice

$Q _ { d } = 100 - 5 P + 0.004 M - 5 P _ { R }$ ,where P is the price of good X, M is income, and $P _ { R }$ is the price of a related good, R.
-If Income is $100,000, the price of the related good is $20, and the supply function is Q_s = 150 + 5P. What is the equilibrium price?

• A) $30
• B) $25
• C) $40
• D) $35
• E) $50

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Definitions:

Pyramids of Numbers

A graphical representation showing the number of organisms at each trophic level in an ecosystem.

Biomass

The total mass of organisms within a given area or ecosystem at a given time, often used as an energy resource.

Gross Primary Productivity

The total amount of solar energy that photosynthetic organisms capture and convert to organic compounds in a given area over a certain period.

Nitrogen Cycle

The worldwide circulation of nitrogen from the abiotic environment into living things and back into the abiotic environment.