The method of tree-ring dating gave the following years A. D. for an archaeological excavation site. Assume that the population of x values has an approximately normal distribution. 1,194 1,250 1,278 1,271 1,268 1,316 1,275 1,317 1,275 A button hyperlink to the SALT program that reads: Use SALT. (a) Use a calculator with mean and standard deviation keys to find the sample mean year x and sample standard deviation s. (Round your answers to four decimal places.)
x =A. D.
s =yr
(b) Find a 90% confidence interval for the mean of all tree ring dates from this archaeological site. (Round your answers to the nearest whole number.)
lower limit A. D.
upper limit A. D.