The immune system<span> is made up of a network of cells, tissues, and organs that work together to protect the body. One of the important cells involved are white blood cells, also called leukocytes, which come in two basic types that combine to seek out and destroy disease-causing organisms or substances.</span>
A,C,D Is the answer to the question
ANSWER:
Its because mother nature tells us herself!
its just like predicting when rhinos will go instinct:
imagine people killing 2 rhinos a week or every two weeks and theres only 500-1000, you can predict that in prob 3-5 years they'll go instinct
so its just like that and they have much higher technology now that it'll just give them the answer without putting much effort into it.
~batmans wife dun dun dun....
The answer is 4Fe+3O2→2Fe2O3
