What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? For all y, if y works, then y is curious. For all y, if y were curious, then y is working. There is at least one y for which if y works, then y is curious.
For all y, y will work if and only if y is curious. For all y, y is curious if and only if y will work. There is at least one y for which y will work if and only if y is curious. There is at least one y for which y is curious if and only if y will work.