[-/0.3 Points] DETAILS BBUNDERSTAT12 7.2.013.S. MY NOTES ASK YOUR TEACHER 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. 1,208 1,313 1,306 1,222 1,268 1,316 1,275 1,317 1,275 LA 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. 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 Need Help? Read It Watch It 3. [-/0.3 Points] DETAILS BBUNDERSTAT12 7.2.013.EP.S. MY NOTES ASK YOUR TEACHER PRA 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. 1,264 1,278 1,250 1,306 1,268 1,316 1,275 1,317 1,275 LA 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. yr (b) When finding an 90% confidence interval, what is the critical value for confidence level? (Give your answer to three decimal places.) t What is the maximal margin of error when finding a 90% confidence interval for the mean of all tree-ring dates from this archaeological site? (Round your answer to the nearest whole number.) E = 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 Need Help? Read !! Watch It MacBook Air