What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? For all x_1, if x_1 were a doctor, then x_1 is an electrician. For all x_1, x_1 is an electrician. For all x_1, if x_1 were an electrician, then x_1 is a doctor.
For all x_1, x_1 is a doctor. For all x_1, x_1 is a doctor if and only if x_1 is an electrician. For all x_1, x_1 is an electrician if and only if x_1 is a doctor.