-Refer to Figure 15-5

question 122

Multiple Choice

-Refer to Figure 15-5. If, because of an externality, the economically efficient output is Q₂ and not the current equilibrium output of Q₁, what does D₂ represent?

• A) the demand curve reflecting external benefits
• B) the demand curve reflecting social benefits
• C) the demand curve reflecting private benefits
• D) the demand curve reflecting the sum of social and external benefits

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Definitions:

Ctenophores

Phylum of marine animals (comb jellies) whose bodies consist of two layers of cells enclosing a gelatinous mass. The outer surface is covered with comblike rows of cilia, by which the animal moves.

Nematocysts

Specialized cells in cnidarians (like jellyfish) that shoot out a toxic barb in self-defense or to capture prey.

Biradially Symmetrical

A type of symmetry in organisms where the body can be divided into mirror-image halves in two different planes.

Cnidarian

A group of aquatic invertebrates known for their stinging cells, including jellyfish, corals, and sea anemones.