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Opportunity cost----The net benefit foregone because the resource providing the service can no longer be used in its next most beneficial use. 機(jī)會(huì)成本——過去的淨(jìng)收益，因爲(wèi)資源所提供的服務(wù)不能再次用於它下一次很有傚的使用。 blog.sina.com.cn