Rapture(23:02:01)
I hope I get it right here: 8 billion times 20m² = 160 billion m². In km² > three 0 less. 160 million km². Nice ok!
Rapture(23:01:10)
I read somewhere that the whole humanity (lets say 8 billion) would fit onto a couple of German states, each person having 20m² (square metres), no floors, all on groundfloor! Ok, so...
Rapture(23:00:31)
Interesting. I had this thought via bicycle. The oneliner is way too small for it, but here goes: