Consider the following premises. t or p. r_2. ~t. r_2 -> q_3. Can we infer q_3 from them? If possible, name the inference rules being used at each step.
 From t or p, ~t we can infer p via disjunctive syllogism. Finally, from r_2 -> q_3, r_2 we can infer q_3 via modus ponens. Therefore, the answer is yes.