Use the information provided to determine a 95% confidence interval for the population variance. A researcher was interested in
the variability in service time (in hours) spent by mechanics fixing the same automotive problem. A random sample was taken resulting in a sample of size 20 from a substantial file of reported experience. The summary statistics are as follows: n = 20, sample mean = 13.8 hours, sample standard deviation = 3.9 hours. Assume service time follows a normal distribution. Round to two decimal places.
2 inch base 2 inch width when crossed shows us symmetrical line on the parallel, which gives us our height of 1 inch as one inch equilateral triangle is formed each side of the symmetrical line.