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Multiple choice questions: Choose the best answer (5 points each) 9. If you were not told what Confidence Level to use, you should choose_ a) 99% because it is the default level to use when you are not given a confidence level. b) 95% because it is the default level to use when you are not given a confidence level. C) 80% because it provides the smallest interval. d) 95% should be used when the confidence interval involves data related to health or medical fields