Find the confidence interval for a One-Sample t-test (Ch.9), given the following info: M = 12.4, n = 20, S.S. = 80 Level of confidence = 99% Hint: as you're doing calculations, don't round any numbers in your calculations to less than two decimal places, or your final answer may be too rounded for you to be able to tell which answer below is correct. Group of answer choices 11.09 < < 13.71 10.78 < < 13.11 10.05 < < 12.88 11.99 < < 14.50