Chemical changes cause a substance to change into an entirely substance with a new chemical formula. Chemical changes are also known as chemical reactions. The “ingredients” of a reaction are called reactants, and the end results are called products.
I would say B because c and d would decrease competition and a would do the same, or just kill the ecosystem.
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the element hydrogen atom is made up of oxygen atoms.
Answer:
increase the rate of reaction.
Explanation:
