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 z, if z makes tea, then z is climbing a mountain. For all z, z will make tea if and only if z will climb a mountain.
For all z, if z makes tea, then z is climbing a mountain can be inferred via the universal biconditional elimination rule. For all z, if z climbs a mountain, then z is making tea can be inferred via the universal biconditional elimination rule.