Think about a company like Amazon and the common "Customers who purchased X also purchased y" feature. If Amazon were to create a classification tree, how many branches and nodes could it have?

举个例子，亚马逊这样的公司常常使用“购买了X的顾客还购买了Y ”特性，如果亚马逊拟创建一个分类树，那么它将需要多少分支和节点？

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But in the past four years, he says, it's become more common for customers to pay in 60 to 90 days.

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One of the most common reasons customers use multiple brands is that they perceive there to be unique benefits associated with each brand used.

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Another common reason that customers use multiple brands is structural barriers that distort demand.

FORBES: The Wallet Allocation Rule and Your Brand