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: If it is windy, then it is cold. It is windy or William is a musician. David is taking a plane. It is cold if and only if William is a musician.
If it is cold, then William is a musician can be inferred via the biconditional elimination rule. If William were a musician, then it is cold can be inferred via the biconditional elimination rule.