What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? For all x_13, if x_13 takes a plane, then x_13 is an astronaut. There is at least one x_13 for which x_13 will take a plane or x_13 will sleep. For all x_13, x_13 is an astronaut if and only if x_13 will sleep.
For all x_13, if x_13 were an astronaut, then x_13 is sleeping. For all x_13, if x_13 sleeps, then x_13 is an astronaut.