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 not cloudy. If Richard were a police officer, then it is cloudy. If Michael were a politician, then it is snowing. Richard is a police officer if and only if it is snowing.
Richard is not a police officer can be inferred via the modus tollens rule. If Richard were a police officer, then it is snowing can be inferred via the biconditional elimination rule. If it snows, then Richard is a police officer can be inferred via the biconditional elimination rule.