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 will play squash or y is not fast. For all y, y will not play squash. For all y, if y plays squash, then y is fast. There is at least one y for which if y were fast, then y is playing squash.
There is at least one y for which y is not fast. For all y, if y were fast, then y is playing squash. There is at least one y for which y is fast if and only if y will play squash. There is at least one y for which y will play squash if and only if y is fast.