Did you know? Diameter of the Earth (12,760 km) is 2 x Mean Radius of the Earth (6,370 km)
Fastest speed attained by a wheeled train (575 km/h)
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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.