A random sample of 19 observations is used to estimate the population mean. The sample mean and the sample standard deviation are calculated as 165.5 and 36.80, respectively. Assume that the population is normally distributed. (You may find it useful to reference the t table.) a. Construct the 95% confidence interval for the population mean. (Round final answer to 2 decimal places.)

b. Construct the 99% confidence interval for the population mean. (Round final answer to 2 decimal places.)