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_4. p_1 or q_3. p_1 <-> p. ~q_4.
~p can be inferred via the modus tollens rule. p_1 -> p can be inferred via the biconditional elimination rule. p -> p_1 can be inferred via the biconditional elimination rule.