A research center claims that 30% of U.S. adults have not purchased a certain brand because they found the advertisements distasteful. You decide to test this claim and ask a random sample of 250 U.S. adults whether they have not purchased a certain brand because they found the advertisements distasteful. Of those surveyed, 90 reply yes. At α = 0.10, is there enough evidence to reject the claim?
a. Verify that np ≥ 5 and nq ≥ 5.
b. Identify the claim and state H0 and Ha.
c. Identify the level of significance α.
d. Find the critical values -z0 and z0 and identify the rejection regions.
e. Find the standardized test statistic z. Sketch a graph.
f. Decide whether to reject the null hypothesis.
g. Interpret the decision in the context of the original claim. |

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