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A technician working for the Chase-National Food Additive Company would like to estimate the preserving ability of a new additive. This additive will be used for Auntie's brand preserves. Based on past tests, it is believed that the time to spoilage for this additive has a standard deviation of 6 days. To be 90% confident of the true mean time to spoilage, what sample size will be needed to estimate the mean time to spoilage with an accuracy of one day ? 27 In the Gallup Poll Monthly, it was reported that 31% of the people surveyed in a recent poll claimed that 8 vegetables were their least favorite food. Surprisingly, only 14% responded with liver, and 10% of those surveyed did not submit a response because they claimed that they liked everything. The poll was based upon a sample of 1001 people. Assuming that a random sample was chosen, construct a 90% confidence interval for the percentage of all Americans who say that vegetables are their least favorite food