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_3, x_3 will work. For all x_3, if x_3 works, then x_3 is taking a plane. For all x_3, x_3 will not take a plane.
Since the premises are contradictory, we can infer anything from them.