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_8 <-> s_3. ~p_8 -> w_1. ~u_4. s_3 <-> u_4.
p_8 -> s_3 can be inferred via the biconditional elimination rule. s_3 -> u_4 can be inferred via the biconditional elimination rule. s_3 -> p_8 can be inferred via the biconditional elimination rule. u_4 -> s_3 can be inferred via the biconditional elimination rule. ~s_3 can be inferred via the biconditional elimination rule.