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20 the compound al(nh3)2 has atoms of nitrogen.

Which best describes the nucleus of an atom a. it is where all of the particle s of the atom are located b. it is the negatively charged part of the atom c. it is where the electrons and the protons are located d. it is the part of the atom with the greatest mass

The picture represents a structure of the respiratory system. which is the function of this structure? to bring air into the body to exchange oxygen with carbon dioxide to carry air to the lungs to release oxygen from the body