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Pop. of Slovenia (2.102million) is 50 x Number of airports in the world (41,800 )
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Height of Olympus Mons (Mars) (21.9 km)
If this was a standard unit ...
Yes, there's now a book based on these numbers. Oxford University Press: July 2018.
Click here to learn more about it.
Click here for Podcast: Andrew Elliott interviewed for New Books Network.