The answer is B. I hope that this helped.
I would say all of the above
Is that an option?
The solid Earth, the largest of Earth's four major spheres. The thin, rocky outer layer of earth and is divided into oceanic and continental crust.
In order for plants to assimilate nitrogen directly into their system, the nitrogen must be in the form of nitrates. Nitrogen in the air and ammonia from decayed matter in the soil is converted to ammonium by decomposers and nitrogen-fixing bacteria. The ammonium is further nitrified to nitrates by nitrifying bacteria. Finally, the nitrates can then absorbed by the plants.
The chemical nature of an atom, that is , the chemical properties of a specific element, is determined by the number of protons in the nucleus<span>. This number of protons is called the </span>atomic number<span>. The mass of the atom, its atomic mass, depends upon both the number of protons and upon the number of neutrons present in the nucleus (remember that the mass of an electron is so small that it is simply ignored for the purpose of establishing the atomic mass).</span>The difference between atoms, ions and isotopes is the number of subatomic particles.<span> An atom is the basic building block of matter, the smallest molecule of an element that exists and that cannot be chemically divided by ordinary means. Each atom is comprised of protons, neutrons and electrons. In ions, the number of electrons differs, and in isotopes.
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