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In a 2003 study the Accreditation Council for Graduate Medical Education found that the medical residents mean number of hours worked in a week is 81.7. Suppose the number of hours worked per week by medical residents is normally distributed with a standard deviation of 6.9. What is the probability that a randomly selected medical resident works: more than 80 hours per week. more than 100 hours per week. less than 60 hours per week. Are any of the above values unusual and why