Question: Voters in a particular city who identify themselves with one or the other of two political parties were randomly selected and asked if they favor a proposal to allow citizens with proper license to carry a concealed handgun in city parks. The results are:
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a. Give a point estimate for the difference in the proportion of all members of Party A and all members of Party B who favor the proposal.
b. Construct the 95% confidence interval for the difference, based on these data.
c. Test, at the 5% level of significance, the hypothesis that the proportion of all members of Party A who favor the proposal is less than the proportion of all members of Party B who do.
d. Compute the p-value of the test.