What would be the speed of rotation if the circumference of earth was 40070​

This country likely has a high total fertility rate (tfr).

I'm pretty sure it's c. extremely gradual but not 100% sure though.

It is useful for historians to write narratives so that history can be passed on from their point of view.  think about a story being told in third person, then think about it again being told in first person, by someone who actually experienced the event.