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: p -> ~q_12. p_4 or q_4. q_4 <-> q_12. p_4 -> q_12.
q_4 -> q_12 can be inferred via the biconditional elimination rule. q_12 -> q_4 can be inferred via the biconditional elimination rule.