With regard to minimizing the impact of groundings caused by engine problems, the existence of two competing engines could help in some situations and hurt in others.

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In her closing remarks, Ms Bokova emphasized the existence of problems that limit access to education for large sections of society.

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But the existence of driverless cars creates new problems.

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Yet the existence of SEC audits, much less problems found, is private.

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He identified three critical problems in Afghanistan: the lack of legitimacy for the government, the existence of safe havens for terrorists across the border in Pakistan, and the lack of military resources.

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Finally, in an interesting twist of logic, he uses the existence of volunteers, of charitable activities, to prove that volunteers and charitable activity cannot solve problems.

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It might also be true that wages are too low, unemployment too high, but the very existence of this organisation shows that state action is not the only way to deal with the problems that result.

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