What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? Name the inference rule being used: w <-> q_11. q_11 or ~w.
w -> q_11 can be inferred via the rewriting rule. w -> q_11 can be inferred via the biconditional elimination rule. q_11 -> w can be inferred via the biconditional elimination rule.