Which of These Normally Heard Sounds Is the Simultaneous Closing

question 1

Multiple Choice

Which of these normally heard sounds is the simultaneous closing of the pulmonary and aortic valves and is heard on the right,second intercostal space?

• A)S1
• B)S2
• C)S3
• D)S4

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Definitions:

Contamination

The presence of unwanted substances or pollutants in the environment or in a material, often causing harm or decreasing quality.

Stratification

The layering or division of society into classes, or the layering of sediments or particles in geological formations.

Surface Freshwater

Bodies of water found on the Earth's surface, such as rivers and lakes, that contain low concentrations of salt.

Great Lakes

A group of five large freshwater lakes located on the border between the United States and Canada, known for being the largest group of freshwater lakes by surface area in the world.