Please help with answering the question below and explain your answer.
In a simple random sample of 821 citizens, 63% said that they approve the tax raise for improving the infra-structure of the nation.
1. What is the margin of error of your estimate of the population proportion at a 95% confidence level?
2. Construct a 95% confidence interval for the proportion of all the people who approve the tax raise for improving the infra-structure of the nation.
3. How large a sample should be taken to estimate this proportion with 95% confidence with a margin of error of no more than 2% points?