Why did the ancient chinese call their land zhongguo, or the middle kingdom?

ok, so basically your gonna start with 350 ok. so there's 60 seconds in a minute so that means you he can go up 10 ft per minute. soo, after 3 minutes he should be at 260 ft after three minutes : )

from my own personal expirence food stamps has alot this makes it eaiser so we can affod bills and so we can life a better lifestyle not needing to worry about paying actual money to buy food since most people spend 100-300 dollars a month on food so this alot so we can afford other bills and other stuff we need

answer:

it caused mass african migration, african populations to grow, african empires to topple, and racism against slaves to emerge.