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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. 1,320 1,236 1,201 1,306 1,268 1,316 1,275 1,317 1,275 LO 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. Submit Answer 5. [-/4.42 Points] DETAILS BBUNDERSTAT12 7.2.014.MI.S. MY NOTES ASK YOUR TEACHER How much does a sleeping bag cost? Let's say you want a sleeping bag that should keep you warm in temperatures from 20F to 45F. A random sample of prices ($) for sleeping bags in this temperature range is given below. Assume that the population of x values has an approximately normal distribution. 60 55 50 35 40 100 30 23 100 110 105 95 105 60 110 120 95 90 60 70 LA USE SALT (a) Use a calculator with mean and sample standard deviation keys to find the sample mean price x and sample standard deviation s. (Round your answers to four decimal places.) X = $ s= $ (b) Using the given data as representative of the population of prices of all summer sleeping bags, find a 90% confidence interval for the mean price u of all summer sleeping bags. (Round your answers to two decimal places.) ower limit upper limit 6. [-/4.42 Points] DETAILS BBUNDERSTAT12 7.2.016.S. MY NOTES ASK YOUR TEACHER Do you want to own your own candy store? Wow! With some interest in running your own business and a decent credit rating, you can probably get a bank loan on startup costs for franchises such as Candy Express, The Fudge Company, Karmel Corn, and Rocky Mountain Chocolate Factory. Startup costs (in thousands of dollars) for a random sample of candy stores are given below. Assume that the population of x values has an approximately normal distribution. 100 175 134 96 75 94 116 100 85 L USE SALT (a) Use a calculator with mean and sample standard deviation keys to find the sample mean startup cost x and sample standard deviation s. (Round your answers to four decimal places.) thousand dollars = thousand dollars (b) Find a 90% confidence interval for the population average startup costs u for candy store franchises. (Round your answers to one decimal place.) lower limit thousand dollars upper limit thousand dollars