A toy manufacturer wants to see how long, on average, a new toy captures children's attention. He tests 20 children selected at random and finds that their mean attention span is 31 minutes with a standard deviation of 4 minutes. If we assume that attention spans are normally distributed, find a 95% confidence interval for the mean attention span of children playing with this new toy. 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? Aa

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