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: Michael is a musician. David is listening to a song or it is windy. Elisabeth is not sleeping. Elisabeth is sleeping if and only if David is listening to a song.
Michael is a musician and Elisabeth is not sleeping can be inferred via the conjunction rule. Elisabeth is not sleeping and Michael is a musician can be inferred via the conjunction rule. If Elisabeth sleeps, then David is listening to a song can be inferred via the biconditional elimination rule. If David listens to a song, then Elisabeth is sleeping can be inferred via the biconditional elimination rule. David is not listening to a song can be inferred via the biconditional elimination rule.