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: For all x, x is a police officer if and only if x will drive a car. There is at least one x for which if x were a police officer, then x is driving a car.
For all x, if x were a police officer, then x is driving a car can be inferred via the universal biconditional elimination rule. For all x, if x drives a car, then x is a police officer can be inferred via the universal biconditional elimination rule.