You subtract the number of protons and the mass to get the number of neutrons.
Scientists suspect that human language evolved around 150000 years ago.
<span>the human language is linked to the Homo Sapiens who lived around 150,000 to 200,000 years ago in eastern or perhaps southern Africa</span>
The reason why scientists suspect this is <span>by evidence of abstract and symbolic behaviour in the early modern humans, taking the form of engravings on red-ochre.
</span>
