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: There is at least one x for which if x cooks, then x is fast. For all x, x is fast if and only if x is a musician.
For all x, if x were fast, then x is a musician can be inferred via the universal biconditional elimination rule. For all x, if x were a musician, then x is fast can be inferred via the universal biconditional elimination rule.