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_9, if x_9 were a police officer, then x_9 is playing a game. There is at least one x_9 for which if x_9 plays a game, then x_9 is taking a plane. For all x_9, x_9 is a police officer or x_9 will not take a plane.
There is at least one x_9 for which if x_9 were a police officer, then x_9 is taking a plane can be inferred via the existential transitivity rule. For all x_9, if x_9 takes a plane, then x_9 is a police officer can be inferred via the universal rewriting rule.