Consider the following premises. forall x_9: P_9(x_9) or Q_9(x_9). forall x_9: ~Q_9(x_9) or R_5(x_9). ~Q_6(c). forall x_9: ~P_9(x_9). Can we infer ~R_5(c) from them?
 From forall x_9: P_9(x_9) or Q_9(x_9), forall x_9: ~P_9(x_9) we can infer forall x_9: Q_9(x_9). From forall x_9: Q_9(x_9) we can infer forall x_9: Q_9(x_9) or Q_6(x_9). From forall x_9: Q_9(x_9) or Q_6(x_9), forall x_9: ~Q_9(x_9) or R_5(x_9) we can infer forall x_9: Q_6(x_9) or R_5(x_9). From forall x_9: Q_6(x_9) or R_5(x_9) we can infer Q_6(c) or R_5(c). Finally, from Q_6(c) or R_5(c), ~Q_6(c) we can infer R_5(c), which contradicts ~R_5(c). Therefore, the answer is no.