Translate the following inference to logic notation: If Robert were a police officer, then Richard is a bartender. If it is cold, then Jessica is playing a game. Robert is a police officer if and only if Jessica is playing a game. If Richard were a bartender, then it is cold. Therefore Richard is a bartender if and only if Robert is a police officer.
p -> q. r -> s. p <-> s. q -> r. Therefore q <-> p.