Consider the following premises. S_10(j) -> p. p -> R(j). forall x_10: R(x_10) -> S_10(x_10). Can we infer p <-> R(j) from them? If possible, name the inference rules being used at each step.
 From forall x_10: R(x_10) -> S_10(x_10) we can infer R(j) -> S_10(j) via universal instantiation. From R(j) -> S_10(j), S_10(j) -> p we can infer R(j) -> p via transitivity. Finally, from p -> R(j), R(j) -> p we can infer p <-> R(j) via biconditional introduction. Therefore, the answer is yes.