Geologic Time Scale.Scientists decide when an era begins<span> and </span>ends<span>, due </span>to<span> mass extinction. ...</span>Scientists determine<span> when drastic changes </span>are<span> made by the fossil record, which shows earths past organisms that have become extinct.</span>
Answer:
You don't want to consume little buggies and germs, would ya?
Explanation:
Make/produce and secrete hormones
Chromosome defect lot of became syndrome.
it's lot of cause
