What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? For all x_5, if x_5 drives a car, then x_5 is a politician. For all x_5, x_5 will write a letter. For all x_5, if x_5 takes a plane, then x_5 is a politician. For all x_5, x_5 will sleep or x_5 will drive a car. For all x_5, if x_5 sleeps, then x_5 is taking a plane.
For all x_5, if x_5 sleeps, then x_5 is a politician.