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: For all y, if y were a nurse, then y is driving a car. For all y, if y drives a car, then y is a nurse. For all y, if y were a nurse, then y is driving a car.
For all y, y is a nurse if and only if y will drive a car can be inferred via the universal biconditional introduction rule. For all y, y will drive a car if and only if y is a nurse can be inferred via the universal biconditional introduction rule. For all y, y will drive a car if and only if y is a nurse can be inferred via the universal biconditional introduction rule. For all y, y is a nurse if and only if y will drive a car can be inferred via the universal biconditional introduction rule.