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Suppose that 80 community delegates discussed the transportation problems on Oahu. 30 of them favor expanding the bus system, 34 favor introduction of rail, and 44 favor building more highways. 15 favor a combination including at least bus expansion and rail, 22 favor a combination including at least rail and more highways, and 21 favor a combination including at least more highways and an expanded bus system, while 12 favor a combination of all three strategies. How many favor only adding more highways? How many favor a combination of an expanded bus system and rail? How many do not like any of the three alternatives