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_2 <-> r_3. r_3 -> t_3. q_4 <-> t_3. ~q_4.
w_2 -> r_3 can be inferred via the biconditional elimination rule. q_4 -> t_3 can be inferred via the biconditional elimination rule. r_3 -> w_2 can be inferred via the biconditional elimination rule. t_3 -> q_4 can be inferred via the biconditional elimination rule. ~t_3 can be inferred via the biconditional elimination rule.