The Average Natural Gas Bill for a Random Sample of 21

question 131

Multiple Choice

The average natural gas bill for a random sample of 21 homes in 19810 zip code during the month of March was $311.90 with a sample standard deviation of $51.60. The 90% confidence interval around this sample mean is ________.

• A) [$285.98, $337.82]
• B) [$292.48, $331.32]
• C) [$278.09. $345.71]
• D) [$266.82, $356.98]

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Definitions:

Spermatic Cord

A bundle of fibers and tissues that run through the abdomen to the testes, containing blood vessels, nerves, and the vas deferens.

Ductus Deferens

A muscular tube in the male reproductive system that transports sperm from the epididymis to the ejaculatory ducts.

Epididymis

A long, coiled tube attached to the back of each testis where sperm mature and are stored.

Testis

A male reproductive organ responsible for the production of sperm and testosterone.