What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? For all x_14, x_14 will work. There is at least one x_14 for which if x_14 takes a plane, then x_14 is a doctor. For all x_14, x_14 will work if and only if x_14 is a doctor.
For all x_14, if x_14 works, then x_14 is a doctor. For all x_14, if x_14 were a doctor, then x_14 is working.