What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? For all x_18, if x_18 were a police officer, then x_18 is a scientist. For all x_18, if x_18 were a police officer, then x_18 is not taking a plane. For all x_18, x_18 is a carpenter or x_18 is an artist. There is at least one x_18 for which if x_18 were an artist, then x_18 is taking a plane. For all x_18, if x_18 were a carpenter, then x_18 is taking a plane. For all x_18, if x_18 were a scientist, then x_18 is a police officer.
There is at least one x_18 for which x_18 will take a plane. For all x_18, x_18 is a police officer if and only if x_18 is a scientist. For all x_18, x_18 is a scientist if and only if x_18 is a police officer.