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: For all x_17, if x_17 cooks, then x_17 is a janitor. If it is overcast, then Barbara is cooking. Barbara is a janitor if and only if it is overcast.
If Barbara were a janitor, then it is overcast can be inferred via the biconditional elimination rule. If it is overcast, then Barbara is a janitor can be inferred via the biconditional elimination rule.