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, if x_4 writes a letter, then x_4 is a soldier. There is at least one x_4 for which if x_4 were a soldier, then x_4 is taking a plane. For all x_4, if x_4 were an artist, then x_4 is taking a plane. For all x_4, x_4 is an artist.
For all x_4, x_4 will take a plane. There is at least one x_4 for which if x_4 writes a letter, then x_4 is taking a plane.