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 z for which if z were rich, then z is reading a book. For all z, if z reads a book, then z is rich. For all z, if z were rich, then z is reading a book.
For all z, z will read a book if and only if z is rich. For all z, z is rich if and only if z will read a book. There is at least one z for which z is rich if and only if z will read a book. There is at least one z for which z will read a book if and only if z is rich.