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: Charles is an artist if and only if it is sunny. Charles is not an artist. It is overcast if and only if it is snowing. It is overcast if and only if it is sunny.
If Charles were an artist, then it is sunny 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 it is overcast, then it is sunny can be inferred via the biconditional elimination rule. If it is sunny, then Charles is an artist can be inferred via the biconditional elimination rule. If it snows, then it is overcast can be inferred via the biconditional elimination rule. If it is sunny, then it is overcast can be inferred via the biconditional elimination rule. It is not sunny can be inferred via the biconditional elimination rule.