Among isotopes of any particular element, the number of can vary, and therefore the mass number of the element will vary.

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Cobalt (co)hoped i

The main types of electromagnetic radiation. radio  waves have  the lowest frequencies  and  longest  wavelengths, while gamma  waves have highest frequencies  and shortest wavelengths. the wavelengths vary across the electromagnetic spectrum from about 10–15 m to more than 104 m.hope it !