Cybersecurity is a critical business issue that demands the attention of business and IT executives. According to a study released by PwC, 38% of surveyed business and IT executives reported phishing scams at their institutions.

Source: Data extracted from “Toward new possibilities in threat management,” PwC, 2017 pwc.to/2kwhPJv.

a. If you conduct a follow-up study to estimate the population proportion of business and IT executives reporting phishing scams at their institutions, would you use a p of 0.38 or 0.50 in the sample size formula?

b. Using your answer in part (a), find the sample size necessary to estimate, with 95% confidence, the population proportion to within ±0.03.