"And because small retailers don't have economies of scale to be able to order a lot of merchandise at once, they are not able to negotiate the best prices or offer the best deals to their shoppers."

VOA: standard.2009.12.20

To make this a first order condition, I'm going to say "at the best response," put a hat over the 1.

为了达到一阶条件,我说在最佳对策下,在S1上写个帽

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