What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? For all x_9, if x_9 plays tennis, then x_9 is a writer. For all x_9, if x_9 were a writer, then x_9 is playing tennis. For all x_9, x_9 is happy or x_9 will play tennis. For all x_9, if x_9 were a writer, then x_9 is drinking water. For all x_9, if x_9 were happy, then x_9 is a writer.
For all x_9, if x_9 plays tennis, then x_9 is drinking water. For all x_9, if x_9 were happy, then x_9 is playing tennis. For all x_9, if x_9 were happy, then x_9 is drinking water. For all x_9, x_9 is a writer. For all x_9, x_9 will play tennis if and only if x_9 is a writer. For all x_9, x_9 is a writer if and only if x_9 will play tennis.