Consider the following premises. ~q_10. p_1 <-> w_1. p_1 -> q_10. u. Can we infer w_1 from them? If possible, name the inference rules being used at each step.
 From p_1 -> q_10, ~q_10 we can infer ~p_1 via modus tollens. Finally, from p_1 <-> w_1, ~p_1 we can infer ~w_1 via biconditional elimination, which contradicts w_1. Therefore, the answer is no.