XXXXXXXXXXIn a study of factors thought to be responsible for the adverse effects of smoking on human reproduction, cadmium level determinations (nanograms per gram) were made on placenta tissue of a...

6.4.10. In a study of factors thought to be responsible for the adverse effects of smoking on human reproduction, cadmium level determinations (nanograms per gram) were made on placenta tissue of a

sample of 14 mothers who were smokers and an independent random sample of 18 nonsmoking mothers. The results were as follows: Nonsmokers: 10.0.8.4. 12.8, 25.0, 11.8.9.8. 12.5, 15.4.23.5, 9.4. 25.1, 19.5. 25.5.9.8. 7.5, 11.8, 12.2, 15.0 Smokers: 30.0, 30.1, 15.0, 24.1, 30.5, 17.8, 16.8, 14.8, 13.4, 28.5, 17.5, 14.4, 12.5, 20.4 Does it appear likely that the mean cadmium level is higher among smokers than nonsmokers? Why do you reach this conclusion?