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: If John plays a game, then Linda is driving a car. If Linda drives a car, then John is playing a game. It is snowing if and only if John is playing a game.
John is playing a game if and only if Linda is driving a car can be inferred via the biconditional introduction rule. Linda is driving a car if and only if John is playing a game can be inferred via the biconditional introduction rule. If it snows, then John is playing a game can be inferred via the biconditional elimination rule. If John plays a game, then it is snowing can be inferred via the biconditional elimination rule.