A small town in the Midwest is located near a regional toxic waste dump. Over the years, there has been an abnormally high instance of cancer among the residents in the town. Many of these residents are unrelated biologically, but have experienced similar types of medical issues. Which perspective best explains the high instance of cancer?
Read DetailsA gardener wants to estimate the average growth of all flowers in the garden after a heavy rain. The gardener measured the height of 14 flowers before and after a heavy rain. It turned out that the mean growth was 1.6 mm with a standard deviation of 0.4 mm. The distribution of the mean growth is mound-shaped and symmetric. The gardener wants to build a 95% confidence interval for the population mean growth. Find the critical t value that is required to construct the 95% confidence interval.
Read DetailsA clinical study is designed to assess the average length of hospital stay of patients who underwent surgery. A preliminary study of a random sample of 70 surgery patients’ records showed that the standard deviation of the lengths of stay of all surgery patients is 6.7 days. How large should a sample to estimate the desired mean to within 1 day at 95% confidence? (Round your answer up to the next higher whole number.)
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