What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? For all x, if x were a scientist, then x is a police officer. For all x, x is not a lawyer. For all x, if x were a police officer, then x is a scientist. There is at least one x for which x is a scientist if and only if x is a lawyer.
For all x, x is a scientist if and only if x is a police officer. For all x, x is a police officer if and only if x is a scientist. There is at least one x for which if x were a scientist, then x is a lawyer. There is at least one x for which if x were a lawyer, then x is a scientist. There is at least one x for which x is not a scientist.