So how long and wide is the flat earth and what is underneath it...

So how long and wide is the flat earth and what is underneath it and how thick is it and what happens at the edges and how are mountains here and what stops fishes and whales falling off the edge and how come the USA hasnt put up a border around the edges of the flat bit and why havent drillers perforated the earth and how does the magnetic field work and why does weather circulate and is the sun flat too and the planets and why do they look so bulbous and what is underneath a mountain and are we all 2 d stick figures as well??
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