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 <-> s_3. ~s. w. s_1.
~s and w can be inferred via the conjunction rule. ~s and s_1 can be inferred via the conjunction rule. w and ~s can be inferred via the conjunction rule. w and s_1 can be inferred via the conjunction rule. s_1 and ~s can be inferred via the conjunction rule. s_1 and w can be inferred via the conjunction rule. s -> s_3 can be inferred via the biconditional elimination rule. s_3 -> s can be inferred via the biconditional elimination rule. ~s_3 can be inferred via the biconditional elimination rule.