Arsenic is a known carcinogen and poison. The standard laboratory procedures for measuri...

Arsenic is a known carcinogen and poison. The standard laboratory procedures for measuring arsenic concentration (mg/L) in water are expensive. Consider the accompanying summary data and Minitab output for comparing a laboratory method to a new relatively quick and inexpensive field method (from the article “Evaluation of a New Field Measurement Method for Arsenic in Drinking WaterSamples,” J. of Envir. Engr., 2008: 382–388).

What conclusion do you draw about the two methods, and why? Interpret the given confidence interval. [Note: One of the article’s authors indicated in private communication that they were unsure why the two methods disagreed.]