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: u_1 <-> q_3. ~u_1. ~t. t <-> w.
~u_1 and ~t can be inferred via the conjunction rule. ~t and ~u_1 can be inferred via the conjunction rule. u_1 -> q_3 can be inferred via the biconditional elimination rule. t -> w can be inferred via the biconditional elimination rule. q_3 -> u_1 can be inferred via the biconditional elimination rule. w -> t can be inferred via the biconditional elimination rule. ~q_3 can be inferred via the biconditional elimination rule. ~w can be inferred via the biconditional elimination rule.