A marketing researcher wants to estimate the mean savings ($) realized by shoppers who showroom. Showrooming is the practice of inspecting products in retail stores and then purchasing the products online at a lower price. A random sample of 100 shoppers who recently purchased a consumer electronics item online after making a visit to a retail store yielded a mean savings of $58. Assume that the population standard deviation is $55. What are the lower and upper limits of the 99% confidence interval estimate for the population the mean savings ($) realized by shoppers who showroom? Lower limit: Upper limit:

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