What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? It is sunny if and only if it is cloudy. Jessica is excited if and only if it is sunny. If it is not cloudy, then Mary is a sailor. If Elisabeth were a taxi driver, then Mary is a sailor. Jessica is not excited.
If it is sunny, then it is cloudy. If Jessica were excited, then it is sunny. If it is cloudy, then it is sunny. If it is sunny, then Jessica is excited. It is not sunny.