In a Random Sample of 12 Calls Made from the U.S.to

question 101

Multiple Choice

In a random sample of 12 calls made from the U.S.to Japan by callers using Skype during the past week, the average call lasted 21.4 minutes, with a sample standard deviation of 5.1 minutes.Assume the population distribution of call times is normal.Build a 99% confidence interval estimate of the average call time for the population of calls represented by the sample (that is, the population of all calls made from the US to Japan last week by callers using Skype) .Report the upper bound for your interval.

• A)28.92
• B)24.01
• C)25.98
• D)22.36
• E)26.89

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Pollution

The introduction of harmful materials into the environment, negatively affecting air, water, and soil quality.

Environmental Assessment

A process used to evaluate the environmental impacts of a proposed project to ensure that decisions are made in an environmentally responsible manner.

EIS

Environmental Impact Statement, a document required for certain actions significantly affecting the quality of the human environment, detailing the impact and alternatives.

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The general population or community at large, especially as it interacts with or is affected by governmental policies or actions.