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: Charles is not driving a car. For all x_1, if x_1 drives a car, then x_1 is taking a plane. For all x_1, x_1 will drive a car or x_1 will not take a plane.
For all x_1, if x_1 takes a plane, then x_1 is driving a car can be inferred via the universal rewriting rule.