Did you know? Circumference of Mars (21,340 km) is 2.5 thousand x Height of K2 mountain (8.61 km)
Pop. of Nanjing, China (8.19 million people)
/fact/population-of-nanjing-china
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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.