What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? For all x, x is an astronaut if and only if x will cook. For all x, x will not cook. There is at least one x for which x will read a book. For all x, x is an astronaut or x is a doctor.
For all x, if x were an astronaut, then x is cooking. For all x, if x cooks, then x is an astronaut. For all x, x is not an astronaut.