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 James makes tea, then it is cold. If Richard were rich, then James is making tea. Richard is rich if and only if James is a janitor. If it is cold, then James is a janitor.
If James makes tea, then James is a janitor can be inferred via the transitivity rule. If Richard were rich, then it is cold can be inferred via the transitivity rule. If Richard were rich, then James is a janitor can be inferred via the biconditional elimination rule. If James were a janitor, then Richard is rich can be inferred via the biconditional elimination rule.