What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? For all x_7, x_7 will play tennis. For all x_7, if x_7 were a taxi driver, then x_7 is listening to a song. For all x_7, x_7 will play tennis if and only if x_7 is a taxi driver.
For all x_7, if x_7 plays tennis, then x_7 is a taxi driver. For all x_7, if x_7 were a taxi driver, then x_7 is playing tennis.