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_16, if x_16 climbs a mountain, then x_16 is an electrician. There is at least one x_16 for which if x_16 were an electrician, then x_16 is a taxi driver. For all x_16, x_16 is a poet if and only if x_16 is a taxi driver. For all x_16, x_16 will take a plane. For all x_16, if x_16 takes a plane, then x_16 is climbing a mountain.
For all x_16, x_16 will climb a mountain can be inferred via the universal modus ponens rule. For all x_16, if x_16 takes a plane, then x_16 is an electrician can be inferred via the universal transitivity rule. There is at least one x_16 for which if x_16 climbs a mountain, then x_16 is a taxi driver can be inferred via the existential transitivity rule. For all x_16, if x_16 were a poet, then x_16 is a taxi driver can be inferred via the universal biconditional elimination rule. For all x_16, if x_16 were a taxi driver, then x_16 is a poet can be inferred via the universal biconditional elimination rule.