What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? If Mary plays a game, then it is overcast. If William drinks water, then Mary is playing a game. If Elisabeth were a bartender, then William is drinking water. If it is overcast, then Charles is an astronaut.
If Mary plays a game, then Charles is an astronaut. If William drinks water, then it is overcast. If Elisabeth were a bartender, then Mary is playing a game.