They can buy into it if they buy into a $15,000 point-of-sales system.

他们可以买入这些数据0,比如价值15000美元的销售网点系统。

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They can be on store shelves for a long period of time, and that has to do with the economics of food, especially food available to the poor, which we'll discuss later.

因此可以在商品货架上销售很长一段时间,这也与食物的经济学价值有关,特别这类食物穷人也买得起,这个我们以后会讨论

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