Is 400,000,000 tonnes as heavy as a Human Brain?
It's about 300,000,000,000 times as heavy as a Human Brain
The weight of a Human Brain is about 0.00135 tonnes.
(adult)
The average weight of an adult human brain is between 0.00135 tonnes. In humans and primates, sight and vision utilize about 30 different parts of the brain which together account for about half of the brain's size.
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