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 were fast, then x_17 is rich. James is not fast. If James were rich, then Barbara is a janitor. Barbara is a janitor if and only if James is fast.
If Barbara were a janitor, then James is fast can be inferred via the biconditional elimination rule. If James were fast, then Barbara is a janitor can be inferred via the biconditional elimination rule.