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8. A student council has 15 members, including Yuko, Luigi, and Justin. a) The staff advisor will select three members at random to be treasurer, secretary, and liaison to the principal. Determine the probability that the staff advisor will select Yuko to be treasurer, Luigi to be secretary, and Justin to be liaison. b) The staff advisor will also select three members at random to clean up after the pep rally. Determine the probability that the staff advisor will select Yuko, Luigi, and Justin to do this