What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? James is drinking water. If Joseph were happy, then James is drinking water. If James drinks water, then Joseph is happy. It is sunny.
Joseph is happy. James is drinking water and it is sunny. It is sunny and James is drinking water. Joseph is happy if and only if James is drinking water. James is drinking water if and only if Joseph is happy.