What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? There is at least one y for which y is an astronaut if and only if y is an office clerk. For all y, y is an office clerk or y will not drink water.
For all y, if y drinks water, then y is an office clerk. There is at least one y for which if y were an astronaut, then y is an office clerk. There is at least one y for which if y were an office clerk, then y is an astronaut.