9. In a sample of seven cars, each car was tested for nitrogen-oxide emissions (in grams per mile) and the following results were obtained: 0.15, 0.08, 0.14, 0.16, 0.17, 0.17, and 0.19. a) Assuming...

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Extracted text: 9. In a sample of seven cars, each car was tested for nitrogen-oxide emissions (in grams per mile) and the following results were obtained: 0.15, 0.08, 0.14, 0.16, 0.17, 0.17, and 0.19. a) Assuming that this sample is representative of the cars in use, construct a 98% confidence interval estimate of the mean amount of nitrogen-oxide emissions for all cars. b) If the EPA requires that nitrogen-oxide emissions be less than 0.165 g/mi, can we safely conclude that this requirement is being met?