What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? If it snows, then it is windy. If it is windy, then Charles is a musician. It is snowing if and only if Susan is a poet.
If it snows, then Charles is a musician. If it snows, then Susan is a poet. If Susan were a poet, then it is snowing.