The question they asked people is: would you go to the window and buy another pair of tickets for $400, having lost them?

他们的问题是：,若票真的丢了,你会去售票窗口，再花400美元买两张票吗？

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So, when you go to two dimensions, you need a pair of numbers.

因此在二维空间里,你需要一对数字来描述

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