What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? If John doesn't drive a car, then Charles is playing a game. If John drives a car, then it is cold. Barbara is a police officer. If it is cold, then John is driving a car. If it is cold, then Barbara is not a police officer.
It is not cold. If John drives a car, then Barbara is not a police officer. John is driving a car if and only if it is cold. It is cold if and only if John is driving a car.