In a 2018 article published in The Lancet, Kappos et al. studied the effect of the drug siponimod in treating patients with secondary progressive multiple sclerosis (SPMS) using a double-blind, randomized, controlled study. Of the 1099 patients given the drug, 198 experienced a severe adverse outcome. Of the 546 patients given the placebo, 82 experienced a severe adverse outcome.

a. Find the percentage in each group that suffered a severe adverse outcome.

b. Create a two-way table with the treatment labels (drug/placebo) across the top.

c. Test the hypothesis that treatment and severe adverse outcome are associated using a significance level of 0.05.