Use the Following Answer Code to Indicate Which Factor Involved

question 242

Multiple Choice

Use the following answer code to indicate which factor involved in the initiation and spread of cardiac excitation is being identified.
-Is the normal pacemaker of the heart.

• A)SA node
• B)AV node
• C)Bundle of His and Purkinje system
• D)Gap junctions

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Definitions:

Variable Input

A production factor that can be adjusted in the short term to change the level of output, such as labor or raw materials.

Fixed Costs

Costs that do not change with the level of output produced by a firm, such as rent, salaries, and equipment costs.

Average Total Cost Curve

A graphical representation of the total cost per unit of output, calculated by dividing the total cost by the quantity of output produced.

Diminishing Marginal Returns

A principle stating that as more of a variable input is added to a fixed input, the additional output from each new unit of input will eventually decrease.