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 z: W_3(z) <-> R_3(z). R_3(a) <-> W_3(a).
R_3(a) -> W_3(a) can be inferred via the biconditional elimination rule. W_3(a) -> R_3(a) can be inferred via the biconditional elimination rule. forall z: W_3(z) -> R_3(z) can be inferred via the universal biconditional elimination rule. forall z: R_3(z) -> W_3(z) can be inferred via the universal biconditional elimination rule.