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: ~q_1. q_1 -> q_4. q_1 or ~q_4.
~q_4 can be inferred via the disjunctive syllogism rule. q_4 -> q_1 can be inferred via the rewriting rule.