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: p_12 <-> s_2. w or p_12. t -> ~s_2. w -> s_2.
p_12 -> s_2 can be inferred via the biconditional elimination rule. s_2 -> p_12 can be inferred via the biconditional elimination rule.