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 if x_9 were a bartender, then x_9 is rich. For all x_9, x_9 is rich if and only if x_9 is curious. For all x_9, if x_9 were a poet, then x_9 is curious. For all x_9, x_9 is a poet.
For all x_9, x_9 is curious can be inferred via the universal modus ponens rule. For all x_9, if x_9 were rich, then x_9 is curious can be inferred via the universal biconditional elimination rule. For all x_9, if x_9 were curious, then x_9 is rich can be inferred via the universal biconditional elimination rule.