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 an artist if and only if x_9 will make tea. For all x_9, x_9 will make tea or x_9 is happy. For all x_9, x_9 is an artist if and only if x_9 is happy.
For all x_9, if x_9 were an artist, then x_9 is happy can be inferred via the universal biconditional elimination rule. There is at least one x_9 for which if x_9 were an artist, then x_9 is making tea can be inferred via the existential biconditional elimination rule. For all x_9, if x_9 were happy, then x_9 is an artist can be inferred via the universal biconditional elimination rule. There is at least one x_9 for which if x_9 makes tea, then x_9 is an artist can be inferred via the existential biconditional elimination rule.