Refer to the Environmental Science & Technology (Jan. 2005) study of methyl tert-butyl ether (MTBE) contamination in New Hampshire wells, presented in Exercise 2.21 (p. 37). Data collected for a sample of 223 wells are saved in the MTBE file. Recall that each well was classified according to its class (public or private) aquifer (bedrock or unconsolidated) and detectable level of MTBE (below limit or detectable).

a. Consider an experiment in which the class, aquifer, and detectable MTBE level of a well are observed. List the sample points for this experiment.

b. Use statistical software to find the number of the 223 wells in each sample point outcome. Then use this information to compute probabilities for the sample points.

c. Find and interpret the probability that a well has a detectable level of MTBE.