A Study Is Going to Be Conducted in Which a Mean

question 80

Multiple Choice

A study is going to be conducted in which a mean of a lifetime of batteries produced by a certain method will be estimated using a 90% confidence interval.The estimate needs to be within +/- 2 hours of the actual population mean.The population standard deviation is estimated to be around 25.The necessary sample size should be at least _______.

• A) 100
• B) 21
• C) 923
• D) 35
• E) 423

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Definitions:

Federal Troops

Military forces deployed by the federal government of a nation, often used for maintaining security, defense, and order, including during times of civil unrest.

Break Down Strikes

The act of forcibly ending or undermining strikes, often through legal, political, or physical means, typically by employers or government authorities.

American President

The head of state and government of the United States of America, elected to a four-year term and responsible for the execution of federal laws and the administration of national policies.

Rutherford B Hayes

was the 19th president of the United States, serving from 1877 to 1881, known for ending the Reconstruction era.