What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? For all x_4, x_4 is a scientist or x_4 will drink water. For all x_4, if x_4 were a scientist, then x_4 is not taking a plane. There is at least one x_4 for which x_4 will take a plane.
There is at least one x_4 for which x_4 is not a scientist.