What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? There is at least one y for which y is a cashier if and only if y is a writer. For all y, y is a politician if and only if y is a writer.
For all y, if y were a politician, then y is a writer. There is at least one y for which if y were a cashier, then y is a writer. For all y, if y were a writer, then y is a politician. There is at least one y for which if y were a writer, then y is a cashier.