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 Susan drives a car, then John is an artist. It is snowing. If John were an artist, then Susan is driving a car. Susan is not driving a car.
John is not an artist can be inferred via the modus tollens rule. It is snowing and Susan is not driving a car can be inferred via the conjunction rule. Susan is not driving a car and it is snowing can be inferred via the conjunction rule. Susan is driving a car if and only if John is an artist can be inferred via the biconditional introduction rule. John is an artist if and only if Susan is driving a car can be inferred via the biconditional introduction rule.