In the article “Nitrate Contamination of Alluvial Groundwaters in the Nakdong River Basin, Korea” (J. Min, S. Yun. et al., Geosciences Journal. 2002:35–46), several chemical properties were measured for water samples taken from irrigation wells at three locations. The following table presents the means, standard deviations, and sample sizes for pH measurements.
Do the data prove conclusively that the pH differs at the different locations?
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