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: For all x_7, x_7 will drink water. For all x_7, if x_7 drinks water, then x_7 is a poet. For all x_7, x_7 is a poet if and only if x_7 is a musician.
For all x_7, x_7 is a poet can be inferred via the universal modus ponens rule. For all x_7, if x_7 were a poet, then x_7 is a musician can be inferred via the universal biconditional elimination rule. For all x_7, if x_7 were a musician, then x_7 is a poet can be inferred via the universal biconditional elimination rule.