What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? There is at least one x_9 for which if x_9 were sad, then x_9 is sleeping. For all x_9, x_9 is sad or x_9 is a taxi driver. For all x_9, if x_9 takes a plane, then x_9 is driving a car. For all x_9, if x_9 goes running, then x_9 is taking a plane. For all x_9, if x_9 drives a car, then x_9 is sleeping. For all x_9, if x_9 were a taxi driver, then x_9 is running.
For all x_9, if x_9 takes a plane, then x_9 is sleeping. For all x_9, if x_9 goes running, then x_9 is driving a car. For all x_9, if x_9 were a taxi driver, then x_9 is taking a plane.