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 if and only if y will take a plane. There is at least one y for which if y takes a plane, then y is playing squash.
For all y, if y plays squash, then y is taking a plane. For all y, if y takes a plane, then y is playing squash.