What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? Karen is not sleeping. If Karen sleeps, then David is fast. If David were fast, then Karen is sleeping. For all x_9, x_9 is fast if and only if x_9 is excited.
David is not fast. For all x_9, if x_9 were fast, then x_9 is excited. For all x_9, if x_9 were excited, then x_9 is fast.