What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? For all x_10, x_10 will work or x_10 is a doctor. For all x_10, x_10 is a scientist. For all x_10, if x_10 works, then x_10 is a writer. For all x_10, x_10 is a doctor if and only if x_10 is a writer.
For all x_10, if x_10 were a doctor, then x_10 is a writer. For all x_10, if x_10 were a writer, then x_10 is a doctor.