What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? Name the inference rule being used: q_20 -> t_1. t -> t_1. ~p_20 or t. p_1 <-> q_8. p_20 or q_20. ~q_8.
q_20 or t can be inferred via the resolution rule. p_1 -> q_8 can be inferred via the biconditional elimination rule. q_8 -> p_1 can be inferred via the biconditional elimination rule. ~p_1 can be inferred via the biconditional elimination rule.