What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? Name the inference rule being used: Sarah is not drinking water. Sarah is drinking water or Barbara is not playing a game. David is sleeping.
Barbara is not playing a game can be inferred via the disjunctive syllogism rule. Sarah is not drinking water and David is sleeping can be inferred via the conjunction rule. David is sleeping and Sarah is not drinking water can be inferred via the conjunction rule. If Barbara plays a game, then Sarah is drinking water can be inferred via the rewriting rule.