The Allegory of the Cave. The dialogue between Socrates and Glaucon is probably fictitious and composed by Plato; whether or not the allegory originated with Socrates, or if Plato is using his mentor as a stand-in for his own idea, is unclear. In the dialogue, Socrates asks Glaucon to imagine a cave, in which prisoners are kept.
The d sublevel consists of five orbitals that can hold a maximum of  two electrons each. The total maximum number of electrons that the  d sublevel can hold is 10 electrons.
since it has four electrons in its outermost orbital it needs four more electrons to complete its octet since it has two electrons in its outermost orbital it needs four more electrons to complete its octet since it has four electrons its outermost orbital it can donate four electrons to complete its octet