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16. Uninsured: It is estimated that 16.6% of all adults in the U.S. are uninsured. You take a random sample of 250 adults seen by a certain clinic and find that 50 are uninsured. (a) In such groups of 250 U.S adults, what is the mean number of those that would be uninsured? (b) What is the standard deviation? (c) In your survey you found 50 of the 250 U.S. adults are uninsured. Would you categorize this number as unusual