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A random sample of 17 health maintenance organizations (HMOS) was selected. For each HMO, the co-payment (in dollars) for a doctor's office visit was recorded. The results are as follows: 9, 12, 10, 11, 7, 7, 6, 12, 9, 5, 6, 10, 9, 11, 6, 10, 8 Under the assumption that co-payment amounts are normally distributed, find a 95% confidence interval for the mean co-payment amount in dollars. Then complete the table below. Carry your intermediate computations to at least three decimal places. Round your answers to one decimal place. (If necessary, consult a list of formulas.) What is the lower limit of the confidence interval? What is the upper limit of the confidence interval