nee help in this probability and statistic question with steps, thank you

Question 1 (10 marks) A traffic research institute is conducting a study on the commuting time of HK residents. From a random sample of 80 workers, it is found that the mean commuting time is 57.2 minutes with standard deviation is 12.5 minutes. Moreover, 62 of them took MTR to work. (a) Construct the 95% confidence interval for the population proportion of residents taking MTR to work. (b) For random samples, each with sample size 80, will be selected periodically. Suppose the 95% confidence interval estimate of the population proportion of residents taking MTR to work have been constructed for 180 independent samples. Approximately how many such intervals can successfully include the true unknown population proportion