An Experiment Was Conducted to Determine the Effectiveness of a Method

question 4

Multiple Choice

An experiment was conducted to determine the effectiveness of a method designed to remove oil wastes found in soil.Three contaminated soil samples were treated.After 95 days,the percentage of contamination removed from each soil sample was measured,with a mean of 49.3 percent and a standard deviation of 1.5 percent.Estimate the mean percentage of contamination removed at a 98 percent confidence level.

• A) \(\left[ \begin{array} { l l }
• 48.36 & 50.24
• \end{array} \right]\)
• B) \([ 43.27 \quad 55.33 ]\)
• C) \(\left[ \begin{array} { l l }
• 47.29 & 51.31
• \end{array} \right]\)
• D) \([ 47.88\)\( \quad\)\( \quad\)\(50.72 ]\)
• E) \([ 46.47 \quad 52.13 ]\)

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Definitions:

Sebaceous Cyst Removal

The surgical procedure to remove a sebaceous cyst, which is a closed sac under the skin filled with a cheese-like or oily material.

Sebum

Oily secretion of the sebaceous glands of the skin.

Excision

The surgical removal of a body tissue, organ, or other entity either completely or partially.

Sebaceous Gland

Glands located under the skin's surface that produce sebum, an oily substance that helps to keep the skin moisturized.