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: David is making tea if and only if it is cloudy. Susan is cooking. David is not making tea. It is cloudy if and only if Michael is a doctor.
Susan is cooking and David is not making tea can be inferred via the conjunction rule. David is not making tea and Susan is cooking can be inferred via the conjunction rule. If David makes tea, then it is cloudy can be inferred via the biconditional elimination rule. If it is cloudy, then Michael is a doctor can be inferred via the biconditional elimination rule. If it is cloudy, then David is making tea can be inferred via the biconditional elimination rule. If Michael were a doctor, then it is cloudy can be inferred via the biconditional elimination rule. It is not cloudy can be inferred via the biconditional elimination rule.