What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? For all y_4, y_4 is an astronaut if and only if y_4 will play tennis. For all y_4, if y_4 plays tennis, then y_4 is an astronaut. For all y_4, y_4 is not an astronaut.
For all y_4, y_4 will not play tennis. For all y_4, if y_4 were an astronaut, then y_4 is playing tennis. For all y_4, if y_4 plays tennis, then y_4 is an astronaut. For all y_4, y_4 will not play tennis.