What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? For all x_2, if x_2 reads a book, then x_2 is a taxi driver. For all x_2, if x_2 were a taxi driver, then x_2 is reading a book. For all x_2, x_2 is a taxi driver if and only if x_2 will read a book.
For all x_2, x_2 will read a book if and only if x_2 is a taxi driver. For all x_2, x_2 is a taxi driver if and only if x_2 will read a book. For all x_2, if x_2 were a taxi driver, then x_2 is reading a book. For all x_2, if x_2 reads a book, then x_2 is a taxi driver.