What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? Name the inference rule being used: There is at least one x_9 for which x_9 is excited if and only if x_9 is bored. For all x_9, if x_9 were bored, then x_9 is playing squash. For all x_9, x_9 is excited.
There is at least one x_9 for which if x_9 were excited, then x_9 is bored can be inferred via the existential biconditional elimination rule. There is at least one x_9 for which if x_9 were bored, then x_9 is excited can be inferred via the existential biconditional elimination rule.