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: r -> ~s. ~u_1. s. u_1 or p.
~r can be inferred via the modus tollens rule. p can be inferred via the disjunctive syllogism rule. ~u_1 and s can be inferred via the conjunction rule. s and ~u_1 can be inferred via the conjunction rule.