Refer to the Behavioral Research and Accounting (January 2015) study

Refer to the Behavioral Research and Accounting (January 2015) study on income tax compliance, Exercise 5.50. Recall that in a sample of 270 U.S. adult workers, the researchers found that 37% prepare their own tax return.
a. Construct a 99% confidence interval for the true proportion of all U.S. adult workers who prepare their own tax return.
b. Suppose an IRS tax consultant claims that 50% of all U.S. adult workers prepare their own tax return. Make an inference about this claim.
c. According to the researchers, about 70% of the sampled workers were recruited from a shopping mall (where they were reimbursed $5 for their time) and about 30% were full-time workers enrolled in a professional graduate degree program. How might this information impact the inference you made in part b?