What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? For all y, y is a mechanic. For all y, y will work or y will climb a mountain. For all y, if y were a mechanic, then y is playing tennis. There is at least one y for which if y works, then y is fast. For all y, if y climbs a mountain, then y is fast.
For all y, y will play tennis. There is at least one y for which y is fast.