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: If it rains, then it is snowing. Michael is cooking or Robert is taking a plane. It is snowing or Michael is not cooking. If Robert takes a plane, then it is raining.
If Robert takes a plane, then it is snowing can be inferred via the transitivity rule. If Michael cooks, then it is snowing can be inferred via the rewriting rule.