What Is the Best Description of the Chest's Mechanical Functions

question 37

Multiple Choice

What is the best description of the chest's mechanical functions?

• A) The chest is a closed space with only one opening; the trachea, to inspire air; the diaphragm contracts down and the intercostal muscles expand the ribs, causing a negative pressure that fills the lungs with air.
• B) The diaphragm contracts, causing the intercostal muscles that are attached to the lungs to also contract, which moves the air into the lungs.
• C) With the chest being an airtight space, the act of breathing occurs when the muscles of the diaphragm and intercostal relax, which causes the lungs to expand and air to flow into the lungs.
• D) The chest is a closed space, and the pleural space surrounds the lungs; when the diaphragm contracts and the intercostals expand, the chest and lungs move outward and downward, allowing expiration and gas exchange in the lungs.

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Definitions:

Sales Revenue

The income received from selling goods or services, which may include discounts and deductions for returned merchandise.

High-low Method

A method applied in cost accounting that calculates variable and fixed costs by analyzing the most and least active periods.

Variable Cost

Variable cost varies directly with the level of output, including costs such as raw materials and direct labor, adjusting according to production volume.

Machine Hours

A measure of the time machines are run in the manufacturing process, used to allocate manufacturing overhead costs.