On the dagram to the right, movemont alone the curve from points it to a to C Il vilrates A. decreasing macphal epeortunty cosit B. Ieflexkve inarginal opportunity costs. C. constant maiginal oppertunity costr. D. Inereasing inarginal opporturyly tosta. .

1. One of the most famous and largest clinical trials ever performed was in 1954. Over 1.8 million
children participated in the clinical trial to determine the effectiveness of the polio vaccine
developed by Jonas Salk. We will focus on the data obtained from the randomized, placebo-
controlled portion of the trial. The question of the interest for the clinical trial was "Does the
vaccine help to prevent polio?" That is, the hypotheses of interest are: H 0 : Treatment
assignment and polio status are statistically independent H A : Treatn ent assignment and polio
status are statistically dependent Below are the observed and expected counts (under the null
hypothesis). Which of the following is the most appropriate test of these hypotheses for these
data? McNemar Test Pearson's Chi-Squared Test Exact McNemar Test Fisher's Exact Test