<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>
<span>a </span>pre-existing condition<span> is a medical condition that started before a person's </span>health insurance<span> went into effect.</span>
Geographic isolation can lead to certain traits becoming more common and can cause certain disabilities to be passed along to the rest of the population at an increased rate. Basically it can cause some traits to become over represented.
Answer:
The ozone layer's status today
And at the end of 2018, the United Nations confirmed in a scientific assessment that the ozone layer is recovering, projecting that it would heal completely in the (non-polar) Northern Hemisphere by the 2030s, followed by the Southern Hemisphere in the 2050s and polar regions by 2060.