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: It is not cold or David is an artist. Michael is not fast or it is snowing. Sarah is not playing tennis. If David were an artist, then Sarah is playing tennis. It is cold or Michael is fast.
David is not an artist can be inferred via the modus tollens rule. Michael is fast or David is an artist can be inferred via the resolution rule.