Which of the Following Muscles Are Considered Primary Muscles of Ventilation

question 68

Multiple Choice

Which of the following muscles are considered primary muscles of ventilation?
I.diaphragm
II.intercostals
III.scalenes
IV
Sternomastoid

• A)I, III, and IV
• B)I and II
• C)III only
• D)I, II, III, and IV

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Definitions:

Total Variable Cost

The sum of all costs that vary with the level of output produced by a company.

Fixed Costs

Costs that do not vary with the level of production or sales.

Short Run

A period in which at least one input, such as plant size or the number of firms in the market, is fixed and cannot be changed.

Fixed Cost

Any cost that does not depend on the firms’ level of output. These costs are incurred even if the firm is producing nothing. There are no fixed costs in the long run.