Which of the Following Phyla Is the Most Successful in the Animal

question 33

Multiple Choice

Which of the following phyla is the most successful in the animal kingdom, based on numbers of species and total biomass?

• A) chordates
• B) vertebrates
• C) mollusks
• D) arthropods
• E) worms

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Definitions:

Average Variable Cost

The cost of labor and materials divided by the quantity of output produced, reflecting costs that change with the level of output.

Average Total Cost

The total cost of production divided by the quantity of output produced; it includes both fixed and variable costs.

Economic Loss

This occurs when total costs exceed total revenue, leading to a negative profit situation.

Marginal Cost

The amount spent to produce an extra unit of a product or service.