Random and independent samples of90recent prime time airings from each of two major networks have been considered. The first network aired a mean of110.6commercials during prime time, with a standard deviation of4.4commercials. The second network aired a mean of109.4commercials, with a standard deviation of4.9commercials. As the sample sizes are quite large, the population standard deviations can be estimated using the sample standard deviations. Construct a90%confidence interval for u1-u2, the difference between the mean number of commercialsu1aired during prime time by the first network and the mean number of commercialsu2aired during prime time by the second network. Then complete the table below. Carry your intermediate computations to at least three decimal places. Round your answers to at least two decimal places. (If necessary, consult alist of formulas.)

What is the lower limit of the 90% confidence interval? What is the upper limit of the 90% confidence interval?

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