What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? Barbara is a poet if and only if Karen is reading a book. If Barbara were a poet, then Robert is a musician. If Robert were a musician, then it is snowing. It is not snowing.
Robert is not a musician. If Barbara were a poet, then Karen is reading a book. If Karen reads a book, then Barbara is a poet.