Suppose germination periods, in days, for grass seed are normally distributed and have a known population standard deviation of 5 days and an unknown population mean. A random sample of 19 types of grass seed is taken and gives a sample mean of 36 days.

Find the confidence interval for the population mean with a 99% confidence level.

z0.10z0.10	z0.05z0.05	z0.025z0.025	z0.01z0.01	z0.005z0.005
1.282	1.645	1.960	2.326	2.576

You may use a calculator or the common z values above.

• Round the final answer to twodecimal places.