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: forall x_8: P_4(x_8) <-> R_4(x_8). exists x_8: W_1(x_8) <-> R_4(x_8).
forall x_8: P_4(x_8) -> R_4(x_8) can be inferred via the universal biconditional elimination rule. exists x_8: W_1(x_8) -> R_4(x_8) can be inferred via the existential biconditional elimination rule. forall x_8: R_4(x_8) -> P_4(x_8) can be inferred via the universal biconditional elimination rule. exists x_8: R_4(x_8) -> W_1(x_8) can be inferred via the existential biconditional elimination rule.