What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? If it is late, then Joseph is reading a book. It is late if and only if it is cloudy. If Joseph reads a book, then it is late. It is not cloudy.
It is late if and only if Joseph is reading a book. Joseph is reading a book if and only if it is late. If it is late, then it is cloudy. If it is cloudy, then it is late. It is not late.