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_8, if x_8 were a doctor, then x_8 is driving a car. For all x_8, if x_8 writes a letter, then x_8 is a doctor. For all x_8, x_8 will write a letter or x_8 will not drive a car.
For all x_8, if x_8 writes a letter, then x_8 is driving a car can be inferred via the universal transitivity rule. For all x_8, if x_8 drives a car, then x_8 is writing a letter can be inferred via the universal rewriting rule.