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: It is cloudy if and only if Richard is rich. It is not cloudy. Richard is rich or it is overcast. If it is overcast, then Michael is a sailor.
If it is cloudy, then Richard is rich can be inferred via the biconditional elimination rule. If Richard were rich, then it is cloudy can be inferred via the biconditional elimination rule. Richard is not rich can be inferred via the biconditional elimination rule.