Update 3 7 globe vs map

3-7-globe-vs-map.md

 In order to switch from the *polar coordinates* (globe) mode to the *Cartesian coordinates* (map box), or vice versa, refer to the *Changing the display mode* part in _[Controlling perspective](3-4-control-perspective)_ section.
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+![](img/3-4-display-mode-compare.png)
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