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_4, if x_4 were a carpenter, then x_4 is cooking. For all x_4, x_4 will take a plane or x_4 is a carpenter. There is at least one x_4 for which if x_4 plays tennis, then x_4 is cooking. For all x_4, x_4 will not take a plane.
For all x_4, x_4 is a carpenter can be inferred via the universal disjunctive syllogism rule.