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: s -> p_16. w_3 <-> q_16. q_16 -> p_16. p_16 -> q_16.
s -> q_16 can be inferred via the transitivity rule. q_16 <-> p_16 can be inferred via the biconditional introduction rule. p_16 <-> q_16 can be inferred via the biconditional introduction rule. w_3 -> q_16 can be inferred via the biconditional elimination rule. q_16 -> w_3 can be inferred via the biconditional elimination rule.