The First Heart Sound, "Lub," Is Caused by the Closure

question 15

Multiple Choice

The first heart sound, "lub," is caused by the closure of the ________ valves.

• A) semilunar
• B) pulmonary
• C) atrioventricular (AV)
• D) aortic

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Definitions:

Input

The resources, materials, or energy used in the production process to generate output.

Factors Of Production

The inputs used in the creation of goods or services in order to make an economic profit, including land, labor, capital, and entrepreneurship.

Input

Resources used in the production of goods and services.

Output

The total amount of goods or services produced by an individual or entity in a given period.