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: Karen is a nurse. Karen is not climbing a mountain. If Jessica listens to a song, then Joseph is drinking water. Karen is climbing a mountain if and only if Joseph is drinking water.
Karen is a nurse and Karen is not climbing a mountain can be inferred via the conjunction rule. Karen is not climbing a mountain and Karen is a nurse can be inferred via the conjunction rule. If Karen climbs a mountain, then Joseph is drinking water can be inferred via the biconditional elimination rule. If Joseph drinks water, then Karen is climbing a mountain can be inferred via the biconditional elimination rule. Joseph is not drinking water can be inferred via the biconditional elimination rule.