The following measurements (in picocuries per liter) were recorded by a set of carbon monoxide detectors installed in a manufacturing facility: 665.8, 661.3, 656.5, 659.3, 658.1 using these measurements, construct a 80% confidence interval for the mean level of carbon monoxide present in the facility. assume the population is approximately normal. copy data step 1 of 4: calculate the sample mean for the given sample data. round your answer to two decimal places.

step 2 of 4:

calculate the sample standard deviation for the given sample data. round your answer to two decimal places.

step 3 of 4:

find the critical value that should be used in constructing the confidence interval. round your answer to three decimal places.

step 4 of 4: construct the 80% confidence interval. round your answer to two decimal places.