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: Michael is fast if and only if Elisabeth is a lawyer. Elisabeth is a lawyer or it is raining. If it rains, then Michael is climbing a mountain. If Michael were fast, then Michael is climbing a mountain.
If Michael were fast, then Elisabeth is a lawyer can be inferred via the biconditional elimination rule. If Elisabeth were a lawyer, then Michael is fast can be inferred via the biconditional elimination rule.