Consider the following premises. p_3 <-> p_1. p -> p_3. Can we infer p -> p_1 from them? If possible, name the inference rules being used at each step.
 From p_3 <-> p_1 we can infer p_3 -> p_1 via biconditional elimination. Finally, from p -> p_3, p_3 -> p_1 we can infer p -> p_1 via transitivity. Therefore, the answer is yes.