Question: Economics and Finance The first question on the U.S. IRS Income Tax Form 1040 asks taxpayers whether they want $3 to go to the Presidential Election Campaign Fund. A large Washington political-action committee obtained a random sample of registered voters and asked them if they checked "Yes" on this question on the past year's return. The results are given in the table below, by party affiliation.
a. Find a 95% confidence interval for the true proportion of registered voters in each political party who checked "Yes" on the Presidential Election Campaign Fund question.
b. Is there any evidence to suggest the proportion of Independent voters who checked "Yes" is different from either the proportion of Democrat or Republican voters who checked "Yes"? Justify your answer.
c. Suppose the results obtained in this study are preliminary and a larger survey is planned. How large a sample is necessary for each political party for the bound on the error of estimation to be 0.02 with confidence level 95%?