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_3, if x_3 were a politician, then x_3 is a mechanic. For all x_3, x_3 will sleep or x_3 will drive a car. There is at least one x_3 for which if x_3 drives a car, then x_3 is reading a book. For all x_3, if x_3 reads a book, then x_3 is a mechanic. For all x_3, x_3 will not sleep or x_3 is a politician.
There is at least one x_3 for which if x_3 drives a car, then x_3 is a mechanic can be inferred via the existential transitivity rule. For all x_3, x_3 will drive a car or x_3 is a politician can be inferred via the universal resolution rule.