Consider the following premises. exists x_6: P_6(x_6) or W(x_6). forall x_6: T_4(x_6) -> Q(x_6). forall x_6: ~P_6(x_6) or T_4(x_6). forall x_6: Q(x_6) <-> W(x_6). Can we infer exists x_6: Q(x_6) from them? If possible, name the inference rules being used at each step.
 From exists x_6: P_6(x_6) or W(x_6), forall x_6: ~P_6(x_6) or T_4(x_6) we can infer exists x_6: W(x_6) or T_4(x_6) via existential resolution. From forall x_6: Q(x_6) <-> W(x_6) we can infer forall x_6: W(x_6) -> Q(x_6) via universal biconditional elimination. Finally, from forall x_6: W(x_6) -> Q(x_6), forall x_6: T_4(x_6) -> Q(x_6), exists x_6: W(x_6) or T_4(x_6) we can infer exists x_6: Q(x_6) via existential disjunction elimination. Therefore, the answer is yes.