A famous mathematician once said "Every question must have a correct answer " for every question one answer."

一位著名的数学家曾说过,“每一个问题都必定有一个正确的答案,每一个人们所回答的问题“

耶鲁公开课 - 政治哲学导论课程节选

Now think of another product in American history that doubled every decade for four decades, and then imagine that that product became the country's, without question, absolute largest export.

思考下在美国历史中有没有另一种产品曾,有如此辉煌的成就,那么这个产品将毫无疑问地,成为美国最大的出口产品

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