In Testing the Difference Between Two Population Means Using Two

question 151

Multiple Choice

In testing the difference between two population means using two independent samples, when is the sampling distribution of the sample mean difference normal?

• A) when the sample sizes are both greater than 30
• B) when the populations are normal
• C) when the populations are non-normal and the sample sizes are large
• D) when the populations are non-normal and the sample sizes are small

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Definitions:

Safety Precaution

Measures taken in advance to prevent accidents or harm in potentially dangerous situations.

Upper Respiratory Infection

An infection affecting the upper part of the respiratory system, including the nose, throat, and bronchi, commonly known as the common cold.

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Personal Protective Equipment; gear worn to minimize exposure to hazards that can cause serious workplace injuries and illnesses.

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The presence of unwanted substances or microorganisms in a material or environment, potentially causing harm or pollution.