A random sample of 11 fields of rye has a mean yield of 47.8 bushels per acre and standard deviation of 9.8 bushels per acre. Determine the 80% confidence interval for the true mean yield. Assume the population is approximately normal. Step 1 of 2: Find the critical value that should be used in constructing the confidence interval. Round your answer to three decimal places.
Step 2 of 2: Construct the 80% confidence interval. Round your answer to one decimal place.