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: If Linda drives a car, then Robert is a taxi driver. If it is cold, then Linda is driving a car. For all z_2, if z_2 were a taxi driver, then z_2 is climbing a mountain.
If it is cold, then Robert is a taxi driver can be inferred via the transitivity rule.