What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? It is raining if and only if William is writing a letter. Jessica is not playing a game or it is raining. William is writing a letter if and only if it is windy. Jessica is playing a game or it is windy.
It is windy or it is raining. If it rains, then William is writing a letter. If William writes a letter, then it is windy. If William writes a letter, then it is raining. If it is windy, then William is writing a letter.