Decomposers are essential in breaking down organic matter into useful ones. For the nitrogen cycle, they break down bodies of dead organisms turning it into ammonia. Also, some bacteria break down nitrates turning into nitrogen which goes back to air.
Answer:
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Explanation:
Many of these diseases can be prevented by the use of viral vaccines, which stimulate protective immunity against the virus without causing major disease. Viral vaccines may also be used in active viral infections, boosting the ability of the immune system to control or destroy the virus.
The Cretaceous–Paleogene (K–Pg) extinction event (also known as the Cretaceous–Tertiary (K–T) extinction) was a sudden mass extinction of three-quarters of the plant and animal species on Earth, approximately 66 million years ago.
The answer for that is B, and E it should be all in your book
