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 overcast if and only if it is snowing. It is not overcast. It is snowing or Jessica is listening to a song. It is cold.
It is not overcast and it is cold can be inferred via the conjunction rule. It is cold and it is not overcast can be inferred via the conjunction rule. If it is overcast, then it is snowing can be inferred via the biconditional elimination rule. If it snows, then it is overcast can be inferred via the biconditional elimination rule. It is not snowing can be inferred via the biconditional elimination rule.