Consider the following premises. forall x_12: Q_12(x_12) -> R_6(x_12). R_6(c) -> p. forall x_12: P(x_12) <-> Q_12(x_12). Can we infer P(c) -> p from them? If possible, name the inference rules being used at each step.
 From forall x_12: P(x_12) <-> Q_12(x_12) we can infer forall x_12: P(x_12) -> Q_12(x_12) via universal biconditional elimination. From forall x_12: P(x_12) -> Q_12(x_12), forall x_12: Q_12(x_12) -> R_6(x_12) we can infer forall x_12: P(x_12) -> R_6(x_12) via universal transitivity. From forall x_12: P(x_12) -> R_6(x_12) we can infer P(c) -> R_6(c) via universal instantiation. Finally, from P(c) -> R_6(c), R_6(c) -> p we can infer P(c) -> p via transitivity. Therefore, the answer is yes.