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 y for which y is a scientist or y will not play tennis. For all y, if y were a musician, then y is playing tennis.
There is at least one y for which if y plays tennis, then y is a scientist can be inferred via the existential rewriting rule.