The article “Effect of Refrigeration on the Potassium Bitartrate Stability and Composition of Italian Wines” (A. Versari, D. Barbanti, et al., Italian Journal of Food Science, 2002:45–52) reports a study in which eight types of white wine had their tartaric acid concentration (in g/L) measured both before and after a cold stabilization process. The results are presented in the following table:
Find a 95% confidence interval for the
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