What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? For all x_1, if x_1 drives a car, then x_1 is playing tennis. For all x_1, if x_1 plays tennis, then x_1 is driving a car.
For all x_1, x_1 will drive a car if and only if x_1 will play tennis. For all x_1, x_1 will play tennis if and only if x_1 will drive a car.