A random sample of 16 pharmacy customers showed the waiting times below (in minutes).

21 28 20 16 13 19 30 22 16 18 19 23 17 20 22 23

Find a 90 percent confidence interval for, assuming that the sample is from a normal population.(Round your standard deviation answer to 4 decimal places and t-value to 3 decimal places. Round your answers to 3 decimal places.)

The 90% confidence interval_____ to _____