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