So just the visible parts, then. As I said, "part of".


Yes, that goof has been addressed.
Only if you want any accuracy in the answer.
Straw man. If no one actually told you the composition of objects, could you still say you knew their density without checking? That's closer to the situation we have with regards to the Universe.

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"If this were play'd upon a stage now, I could condemn it as an improbable fiction."
Shakespeare, Twelfth Night
Illuminati's Razor-The most complicatedly evil answer is usually the most correct answer. - Fazor
"Every book is a children's book if the kid can read." - Mitch Hedberg
"Distance doesn’t matter much in space, where if you just start a thing off with the right kind of shove, sooner or later it will get where you want it to go." -Frederik Pohl, Mining the Oort