What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? Joseph is a sailor if and only if it is snowing. Joseph is a sailor if and only if Thomas is happy. If it snows, then Thomas is happy.
If Joseph were a sailor, then it is snowing. If Joseph were a sailor, then Thomas is happy. If it snows, then Joseph is a sailor. If Thomas were happy, then Joseph is a sailor.