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 David were an artist, then it is late. It is windy if and only if David is an artist. If it is late, then David is an artist. It is not windy.
David is an artist if and only if it is late can be inferred via the biconditional introduction rule. It is late if and only if David is an artist can be inferred via the biconditional introduction rule. If it is windy, then David is an artist can be inferred via the biconditional elimination rule. If David were an artist, then it is windy can be inferred via the biconditional elimination rule. David is not an artist can be inferred via the biconditional elimination rule.