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 an artist, then x_18 is taking a plane. For all x_18, x_18 will take a plane if and only if x_18 is an electrician. There is at least one x_18 for which x_18 will make tea or x_18 is an artist. For all x_18, x_18 is sad. For all x_18, if x_18 makes tea, then x_18 is an electrician.
For all x_18, if x_18 takes a plane, then x_18 is an electrician. For all x_18, if x_18 were an electrician, then x_18 is taking a plane.