What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? For all y, if y were happy, then y is a sailor. For all y, if y were a sailor, then y is happy. For all y, y will not drive a car. For all y, y is happy if and only if y will drive a car.
For all y, y is happy if and only if y is a sailor. For all y, y is a sailor if and only if y is happy. For all y, if y were happy, then y is driving a car. For all y, if y drives a car, then y is happy. For all y, y is not happy.