The lifetime (in hours) of a 60-watt light bulb is a random variable that has a Normal distribution with = 30 hours.A random sample of 25 bulbs put on test produced a sample mean lifetime of 
= 1038.Construct a 92% confidence interval estimate for the mean lifetime .If it were desired to cut the confidence interval to half its length while keeping the same 92% level,what size sample would be required to achieve this?
Definitions:
Type C
A personality type characterized by emotional suppression, detail orientation, and a high level of conscientiousness; sometimes linked to increased stress-related illness risk.
Coronary Heart Disease
A condition characterized by the impairment of the heart's blood supply due to plaque buildup in the coronary arteries, leading to heart attacks and angina.
Eclectic View
An approach that combines methods and theories from various schools of thought to address psychological issues.
Psychologists
Professionals who study mental processes and behavior in humans and animals through observation, experimentation, and analysis.
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