最高配置的13寸吋Air则采用了速度稍快一筹的1.7GHz处理器，内存和闪存都增加一倍。 用户还可以选择扩展内存（仅限11寸吋版）、选用更快的处理器、扩展存储空间。

That model also has additional options for more RAM (for the 11-inch), a faster processor, and more storage.

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dom4j 文档对象模型不仅速度快、内存使用高效，并且提供了很好的可扩展性。

The dom4j document object model is fast, memory-efficient, and also offers great extensibility.

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