What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? For all x_7, if x_7 takes a plane, then x_7 is a janitor. For all x_7, if x_7 were an office clerk, then x_7 is taking a plane. For all x_7, x_7 will climb a mountain or x_7 is an office clerk. For all x_7, if x_7 climbs a mountain, then x_7 is a janitor. For all x_7, x_7 is not a janitor or x_7 is excited.
For all x_7, if x_7 were an office clerk, then x_7 is a janitor.