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_10 for which x_10 will make tea if and only if x_10 is a bartender. For all x_10, if x_10 drinks water, then x_10 is a bartender. For all x_10, if x_10 were a bartender, then x_10 is drinking water.
For all x_10, x_10 will drink water if and only if x_10 is a bartender can be inferred via the universal biconditional introduction rule. For all x_10, x_10 is a bartender if and only if x_10 will drink water can be inferred via the universal biconditional introduction rule. There is at least one x_10 for which if x_10 makes tea, then x_10 is a bartender can be inferred via the existential biconditional elimination rule. There is at least one x_10 for which if x_10 were a bartender, then x_10 is making tea can be inferred via the existential biconditional elimination rule.