图中每个机场的最长的跑道的长度是以单元英尺来存储的。我们可以用一个简单的math步骤把值转化成以米为单位。
The length of the longest runway at each airport in the graph is stored as units of feet. We can use a
simple math step to convert that value to meters.
在查询语句中加上一个project步骤，我们可以让结果更有意义一些。
We could make the result a bit more interesting by adding a project step to the query.
