Consider the following premises. p or w. s. u -> r_10. w -> u. p -> r_10. Can we infer r_10 and s from them? If possible, name the inference rules being used at each step.
 From w -> u, u -> r_10 we can infer w -> r_10 via transitivity. From p -> r_10, w -> r_10, p or w we can infer r_10 via disjunction elimination. Finally, from r_10, s we can infer r_10 and s via conjunction. Therefore, the answer is yes.