What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? William is writing a letter if and only if Linda is a server. For all x_19, x_19 will play a game if and only if x_19 is a server. If Linda plays a game, then William is writing a letter.
If William writes a letter, then Linda is a server. If Linda were a server, then William is writing a letter. For all x_19, if x_19 plays a game, then x_19 is a server. For all x_19, if x_19 were a server, then x_19 is playing a game.