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: William is bored if and only if Sarah is a soldier. If Karen were a musician, then James is a nurse. James is not a nurse. If William were bored, then Karen is a musician.
Karen is not a musician can be inferred via the modus tollens rule. If William were bored, then Sarah is a soldier can be inferred via the biconditional elimination rule. If Sarah were a soldier, then William is bored can be inferred via the biconditional elimination rule.