卖家数量很多，规模很小，每个生产者都不能影响价格，商品价格完全由供给和需求来决定的市场结构是（）
B
暂无解析
Inthepast,peopleusedtotravelabroadtolookmanydifferences.Nowadays,placesallovertheworldaremoreandmoresimilar.Whatarethecausesofthesimilarity?Doyouthinktheadvantagesofthisproblemoutweighthedisadvantages?
-----Wouldyoumindmyusingyourpen?
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