One way to give a relative value of electronegativity is based on the ionization energy and the electron affinity of the element. The EN value can be calculated using the equation:  EN = k(I - EA). Identify the statements that correctly describe why electronegativity is based on ionization energy and electron affinity.

(i) Ionization energy measures how difficult it is to remove electrons, which can be a reflection of how strong an electron in the atom is attracted to its nucleus.
(ii) Electron affinity measures how difficult it is to add electrons, which can be a reflection of how strong an electron in another atom is attracted to its nucleus.
(iii) Ionization energy and Electron affinity both measure how negative the energies are in the addition and removal of electrons.
(iv) Electron affinity and electronegativity are the same.