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_5, x_5 will play tennis. For all x_5, x_5 will not play tennis. There is at least one x_5 for which x_5 is an electrician.
Since the premises are contradictory, we can infer anything from them.