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_12(a_12). s -> p_3. forall x_12: R_12(x_12) or S_12(x_12). t -> p_3. s or t.
p_3 can be inferred via the disjunction elimination rule.