Contour lines and relief

你需要知道的

• Contour lines join places at the same height.
• Lines packed close together mean a steep slope, and lines spread far apart mean a gentler slope.
• Rings that get smaller and smaller mark a peak.
• Every fifth line is a thicker index contour with the height written on it, and the height change from one line to the next stays the same.

这个短片讲了

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