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 z, z will drive a car if and only if z is a nurse. There is at least one z for which z is a nurse or z will not drive a car.
There is at least one z for which if z drives a car, then z is a nurse can be inferred via the existential rewriting rule. For all z, if z drives a car, then z is a nurse can be inferred via the universal biconditional elimination rule. For all z, if z were a nurse, then z is driving a car can be inferred via the universal biconditional elimination rule.