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: Susan is climbing a mountain or William is not a poet. Susan is climbing a mountain if and only if William is a poet.
If William were a poet, then Susan is climbing a mountain can be inferred via the rewriting rule. If Susan climbs a mountain, then William is a poet can be inferred via the biconditional elimination rule. If William were a poet, then Susan is climbing a mountain can be inferred via the biconditional elimination rule.