An analytical method for determining residual nickel content in shortening was tested against a standard containing exactly 1.626% Ni. The results obtained for percent residual Ni were as follows: 1.608, 1.626, 1.626, 1.629, 1.630, 1.606.
Has a significant error been demonstrated at the 95% confidence interval? Answer should be either yes or no
http://www.stat.yale.edu/Courses/1997-98/101/confint.htm
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