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 snowing. It is snowing if and only if it is overcast. Karen is not climbing a mountain. Karen is climbing a mountain if and only if Karen is a sailor.
It is not snowing and Karen is not climbing a mountain can be inferred via the conjunction rule. Karen is not climbing a mountain and it is not snowing can be inferred via the conjunction rule. If it snows, then it is overcast can be inferred via the biconditional elimination rule. If Karen climbs a mountain, then Karen is a sailor can be inferred via the biconditional elimination rule. If it is overcast, then it is snowing can be inferred via the biconditional elimination rule. If Karen were a sailor, then Karen is climbing a mountain can be inferred via the biconditional elimination rule. It is not overcast can be inferred via the biconditional elimination rule. Karen is not a sailor can be inferred via the biconditional elimination rule.