The prices of a random sample of 20 new motorcycles have a sample standard deviation of $3900.

Question:

The prices of a random sample of 20 new motorcycles have a sample standard deviation of $3900. Use a 90% level of confidence.
Assume the sample is from a normally distributed population and construct the indicated confidence intervals for
(a) The population variance σ2
(b) The population standard deviation σ. Interpret the results.