I think it is sun quacks. It is based on expert judgement.<span />
<span>Its components are visible. --heterogenous
It may be mistaken for a pure substance. --homogenous
It can be separated using distillation. --homogenous
Concrete is an example of this kind of mixture. --heterogenous
Hope this helps!</span>
C. From carbon dioxide in the atmosphere
The heart is beneath the breastbone in the chest cavity of the frog
