Clearly state, what do you understand by the terms `:` mass number, nucleaons and nuclides?

Explanation

Mass number `:` The mass number `A` of an atom is the integer nearest ot the relative atomic mass and is equal to the number of nucleons in the nucleus.
Nucleons `:` The sub`-` atomic particles of the nucleus of an atom are callec nucleons. Protons, neutrons are examples of neceons.
Nuclides `:` Particular nuclear nuclear species with a specific atomic number and a mass number is referred to as nuclide.