The commute times for workers in a city are normally distributed with an unknown population mean and standard deviation. If a random sample of 20 workers is taken and results in a sample mean of 21 minutes and sample standard deviation of 6 minutes, find a 95% confidence interval estimate for the population mean using the Student's 1-distribution The margin of error for a 95% confidence interval estimate for the population mean using the Student's t-distribution is 2.81 . Find a 95% confidence interval estimate for the population mean using the Student's I-distribution Round the final answers to two decimal places