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, if x_7 drives a car, then x_7 is a sailor. For all x_7, if x_7 were rich, then x_7 is driving a car. There is at least one x_7 for which x_7 is rich or x_7 is not a sailor.
For all x_7, if x_7 were rich, then x_7 is a sailor can be inferred via the universal transitivity rule. There is at least one x_7 for which if x_7 were a sailor, then x_7 is rich can be inferred via the existential rewriting rule.