Which Type of Bird Is Most Likely to Need Air

question 63

Multiple Choice

Which type of bird is most likely to need air sacs to reduce its weight?

• A) birds that migrate long distances
• B) waterfowl that float on water, but do not dive
• C) birds that spend much of their time underwater
• D) ratites

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Definitions:

Marginal Cost

The growth in total expenses incurred from making one more unit of a product or service.

High-Quality Hydraulic

Refers to hydraulic systems or components that are characterized by superior performance, durability, and efficiency.

Marginal Cost

The extra expense involved in creating an additional unit of a product or service.

Variable Costs

Costs that vary directly with the level of production or the volume of output.