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