Hi i need help with these questions please.

3) If a sample of 200 Boston residents is taken, there is probability 0.99 that the sample mean gross monthly will fall between what two values, symmetric around the mean? Round your answers to at least two decimal places.

4) The report indicates that 18.7% of Boston residents live below the poverty threshold. If a sample of 50 residents is selected at random, what is the probability that more than 20% of the residents in that sample live below the poverty threshold? Round your answer to at least three decimal places. Hint: Express percentages as proportions before starting your calculations.

5) In a sample of 50 residents, there is probability 0.90 that the sample proportion living below the poverty threshold will fall between what two values, symmetric around the mean?