Environmental Science and Technology Oct 1993 reported a stu

Environmental Science and Technology (Oct., 1993) reported a study of contaminated soil lathe Netherlands. Seventy-two (n = 72) 400 gram soil specimens were sampled, dried, and analyzed for the contaminant cyanide. You can treat this as a large sample and use a z-score for your test. The cyanide concentration (in milligrams per kilogram - mg/kg -_of soil) of each specimen was determined using an Infrared microscope method. The sample resulted In the following data Test the hypothesis that the true mean cyanide level in the soil is less than 100 mg/kg. Use alpha =.10 Would you reach the same conclusion as part 1 using alpha =.05? alpha =.01? Why can the conclusion of a test change when the value of alpha is changed?

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