help me solve

1) In a survey of 4013 adults, 722 say they have seen a ghost. Construct a 90% confidence interval for the proportion of people who say they have seen a ghost.

Show your value for E and your confidence interval

2)You are running a political campaign and wish to estimate, with 95% confidence, the proportion of registered voters who will vote for your candidate. Your estimate must be within 3% of the true population. Find the minimum sample size if a preliminary estimate tells you that 31% of the voters will vote for your candidate.