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I. Professor Hur Munir and JB Kim from 'KH SciV University' recently got funding from the mp3 player manufacturing company 'Hurricane and Tornado'. Since the company wants to check how its product inuence people's mental health, the two professors decide to conduct an experiment to help the company. They seek volunteers for the experiment and draws some respondents. Of these respondents, 3 people are below age twenty, 6 are at the age between twenty and twentynine, 4 are in the thirty to thirtynine age group and 2 are over thirtynine. The researcher will randomly select 5 persons to assign to a particular treatment regimen. Find the probability that: (Simplify your results to one irreducible fraction) (a) at least 3 are over age thirty. (b) either exactly 2 over twentynine or exactly 3 below thirty are chosen. II. How many distinguishable letter arrangements can be made from the letters 'IMISSJUNGSOONBONG' where the G's are exactly two letters apart? (You don't need to simplify your results to one irreducible fraction.)