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_10 for which if x_10 were excited, then x_10 is a janitor. For all x_10, x_10 is a mechanic if and only if x_10 is a janitor. For all x_10, if x_10 were a janitor, then x_10 is excited.
There is at least one x_10 for which x_10 is excited if and only if x_10 is a janitor. There is at least one x_10 for which x_10 is a janitor if and only if x_10 is excited. For all x_10, if x_10 were a mechanic, then x_10 is a janitor. For all x_10, if x_10 were a janitor, then x_10 is a mechanic.