Consider the following premises. p_11 -> t_3. ~s. p <-> p_11. t_3 -> s. Can we infer ~p from them? If possible, name the inference rules being used at each step.
 From p_11 -> t_3, t_3 -> s we can infer p_11 -> s via transitivity. From p <-> p_11 we can infer p -> p_11 via biconditional elimination. From p -> p_11, p_11 -> s we can infer p -> s via transitivity. Finally, from p -> s, ~s we can infer ~p via modus tollens. Therefore, the answer is yes.