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