Life Tests Performed on a Sample of 13 Batteries of a New

question 83

Multiple Choice

Life tests performed on a sample of 13 batteries of a new model indicated: (1) an average life of 75 months, and (2) a standard deviation of 5 months.Other battery models, produced by similar processes, have normally distributed life spans.The 90% confidence interval for the population mean life of the new model is _________.

• A)66.78 to 83.23
• B)72.72 to 77.28
• C)72.53 to 77.47
• D)66.09 to 83.91
• E)73.34 to 76.25

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Definitions:

Social Phobia

Also known as Social Anxiety Disorder, it is an intense fear of social situations where one might be judged or scrutinized by others.

Anxiety Disorder

A group of mental health disorders characterized by significant feelings of anxiety and fear, often leading to behavioral disturbances and physical symptoms.

Motor Tension

Physical manifestations of stress or anxiety, often including muscle tightness or aches.

Apprehensive Expectations

Feelings of anxiety or worry about future events or outcomes, often based on anticipated threats or negative experiences.