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Question
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. If we wished to narrow the boundary around μ for a 98 percent confidence interval to within 0.5 percent, how many soil samples should be in our experiment.A. 437
B. 33
C. 9
D. 6
E. 3
Answer
This answer is hidden. It contains 40 characters.
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