For a Given Level of Precision and Confidence Level, a Researcher

question 24

Multiple Choice

For a given level of precision and confidence level, a researcher determines that he needs a sample size of 400. The study was to find out that the proportion of people who smoke is 30 percent. For the same level of precision and confidence, she would have needed the same sample size if the proportion of those who smoked were to change to:

• A)40 percent.
• B)50 percent.
• C)60 percent.
• D)70 percent.
• E)As long as the precision and confidence stay the same, the proportion doesn't affect the required sample size.

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Definitions:

Myelin

A fatty substance that surrounds the axon of some nerve cells, forming an insulating layer that is essential for the proper functioning of the nervous system, speeding up the transmission of nerve impulses.

Saltatory Conduction

A process whereby nerve impulses jump between gaps in the myelin sheath of neurons, speeding up signal transmission.

Nodes

Points of intersection or branching in a network or circuit, often used in the context of biological and technological systems.

Sodium Channels

Ion channels found in cell membranes that allow sodium ions to flow into or out of cells, playing a crucial role in generating and transmitting electrical signals.