Consider the following premises. s_1 -> Q(h_3). s_1 or ~Q_4(h_3). forall y: Q(y) -> Q_4(y). Can we infer s_1 <-> Q_4(h_3) from them? If possible, name the inference rules being used at each step.
 From forall y: Q(y) -> Q_4(y) we can infer Q(h_3) -> Q_4(h_3) via universal instantiation. From s_1 or ~Q_4(h_3) we can infer Q_4(h_3) -> s_1 via rewriting. From s_1 -> Q(h_3), Q(h_3) -> Q_4(h_3) we can infer s_1 -> Q_4(h_3) via transitivity. Finally, from s_1 -> Q_4(h_3), Q_4(h_3) -> s_1 we can infer s_1 <-> Q_4(h_3) via biconditional introduction. Therefore, the answer is yes.