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 Charles drives a car, then Linda is excited. If Linda were excited, then Charles is driving a car. If Charles drives a car, then Linda is excited.
Charles is driving a car if and only if Linda is excited can be inferred via the biconditional introduction rule. Linda is excited if and only if Charles is driving a car can be inferred via the biconditional introduction rule. Linda is excited if and only if Charles is driving a car can be inferred via the biconditional introduction rule. Charles is driving a car if and only if Linda is excited can be inferred via the biconditional introduction rule.