D. a warm front causes rain showers to occur over a particular area for several days
Average atomic mass listed for nitrogen in the periodic table is 14
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Isotopes of any given factor all incorporate the equal variety of protons, so they have the identical atomic wide variety (for example, the atomic wide variety of helium is usually 2). Isotopes of a given factor include exceptional numbers of neutrons, therefore, special isotopes have special mass numbers.
