Answer
See step by step work for proof.
Work Step by Step
An unsatisfiable compound proposition is always false and thus is equivalent with F. The negation of the unsatisfiable compound proposition is then equivalent with t and is thus always true, this means that the negation of the unsatisfiable compound proposition is a tautology.
A tautology is always true and is thus equivalent with T. The negation of the tautology is then equivalent with F and is thus always false, this means that the negation of a tautology is unsatisfiable.