The article "Fish Oil Staves Off Schizophrenia" (USA Today, February 2, 2010) describes a study in which 81 patients age 13 to 25 who were considered at-risk for mental illness were randomly assigned to one of two groups. Those in one group took four fish oil capsules daily. The other group took a placebo. After 1 year, 5% of those in the fish oil group and 28% of those in the placebo group had become psychotic. Is it appropriate to use the two-sample z test of this section to test hypotheses about the difference in the proportions of patients receiving the fish oil and the placebo treatments who became psychotic? Explain why or why not.