A researcher wants to know whether the acidity of rain (pH) near Houston, Texas, is signicantly different

A researcher wants to know whether the acidity of rain (pH) near Houston, Texas, is significantly different from that near Chicago, Illinois. He randomly selects 12 rain dates in Texas and 14 rain dates in Illinois and obtains the following data:

(a) Is the sampling method dependent or independent? Why?
(b) Because the sample sizes are small, what must be true regarding the populations from which the samples were drawn?
(c) Draw side-by-side boxplots of the data. What does the visual evidence imply about the pH of rain in the two states?
(d) Does the evidence suggest that there is a difference in the pH of rain in Chicago and Houston? Use the α = 0.05 level of significance.

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Texas 4.65 4.71 510 5.22 4.46 4.93 5.22 4.76 4.25 5.14 4.11 Illinois 4.40 4.9 4.22 4.64 .54 4.35 4.69 4.40 4.75 4.63 4.45 4.49 4.36 4.52