Is the Earth perfectly round?
True — Earth is round, but not a perfect sphere; it's an oblate spheroid, slightly flattened at the poles and bulging at the equator due to its spin.
Is the Great Wall of China visible from space?
False — astronauts have confirmed the Great Wall isn't visible to the naked eye from orbit. It's too narrow and blends into the landscape.
Is there gravity in space?
False — there's plenty of gravity in space. Astronauts float because they're falling, not because gravity is gone.