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_7 for which if x_7 were an astronaut, then x_7 is a janitor. For all x_7, x_7 is a janitor if and only if x_7 will play squash. For all x_7, x_7 will not play squash.
For all x_7, if x_7 were a janitor, then x_7 is playing squash. For all x_7, if x_7 plays squash, then x_7 is a janitor. For all x_7, x_7 is not a janitor.