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According to one consumer credit reporting agency, Canadians in the age group 65+ have the best credit scores. Suppose the credit scores of all 65+ Canadians have a normal distribution with a mean of 750 and a standard deviation of 123. Find the probability that the mean credit score of a random sample of 25 Canadians from this age group is (Note: Round your answers to four decimals.) a. less than 690 = Number b. more than 810 = Number c. between 690 and 810 = Number