So,this country's track record around staging and managing safe events is equal to nonein the world."

VOA: standard.2009.06.12

That says that if you have independent probabilities, then the probability of two events is equal to the product of their probabilities.

意思是,几个相互独立的事件,其中两个事件同时发生的概率,等于他们分别发生的概率的乘积

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