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 y_2, y_2 will take a plane if and only if y_2 is a musician. For all y_2, y_2 is a police officer if and only if y_2 will play tennis. For all y_2, y_2 will take a plane or y_2 will play tennis. For all y_2, if y_2 were a police officer, then y_2 is a musician.
For all y_2, if y_2 takes a plane, then y_2 is a musician can be inferred via the universal biconditional elimination rule. For all y_2, if y_2 were a police officer, then y_2 is playing tennis can be inferred via the universal biconditional elimination rule. For all y_2, if y_2 were a musician, then y_2 is taking a plane can be inferred via the universal biconditional elimination rule. For all y_2, if y_2 plays tennis, then y_2 is a police officer can be inferred via the universal biconditional elimination rule.