Consider the following premises. ~p. q <-> ~p_7. p_7 -> p. Can we infer q from them? If possible, name the inference rules being used at each step.
 From p_7 -> p, ~p we can infer ~p_7 via modus tollens. From q <-> ~p_7 we can infer ~p_7 -> q via biconditional elimination. Finally, from ~p_7 -> q, ~p_7 we can infer q via modus ponens. Therefore, the answer is yes.