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 Michael were a taxi driver, then William is cooking. For all x_12, if x_12 were happy, then x_12 is a taxi driver. If William cooks, then Michael is happy.
If Michael were a taxi driver, then Michael is happy can be inferred via the transitivity rule.