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: If it snows, then it is overcast. If it is overcast, then it is snowing. If it is overcast, then it is snowing.
It is snowing if and only if it is overcast can be inferred via the biconditional introduction rule. It is snowing if and only if it is overcast can be inferred via the biconditional introduction rule. It is overcast if and only if it is snowing can be inferred via the biconditional introduction rule. It is overcast if and only if it is snowing can be inferred via the biconditional introduction rule.