A certain counselor wants to compare mean IQ scores for two different social groups. A random...

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A certain counselor wants to compare mean IQ scores for two different social groups. A random sample of 14 IQ scores from group 1 showed a mean of 88 and a standard deviation of 15, while an independently chosen random sample of 9 IQ scores from group 2 showed a mean of 80 and a standard deviation of 14. Assuming that the populations of IQ scores are normally distributed for each of the groups and that the variances of these populations are equal, construct a 90% confidence interval for the difference u,- u, between the mean u, of IQ scores of group 1 and the mean u, of IQ scores of group 2. Then complete the table below. Carry your intermediate computations to at least three decimal places. Round your responses to at least two decimal places. (If necessary, consult a list of formulas.) What is the lower limit of the 90% confidence interval? What is the upper limit of the 90% confidence interval? A certain counselor wants to compare mean IQ scores for two different social groups. A random sample of 14 IQ scores from group 1 showed a mean of 88 and a standard deviation of 15, while an independently chosen random sample of 9 IQ scores from group 2 showed a mean of 80 and a standard deviation of 14. Assuming that the populations of IQ scores are normally distributed for each of the groups and that the variances of these populations are equal, construct a 90% confidence interval for the difference u,- u, between the mean u, of IQ scores of group 1 and the mean u, of IQ scores of group 2. Then complete the table below. Carry your intermediate computations to at least three decimal places. Round your responses to at least two decimal places. (If necessary, consult a list of formulas.) What is the lower limit of the 90% confidence interval? What is the upper limit of the 90% confidence interval?