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 will take a plane or y is not a police officer. For all y, if y drinks water, then y is writing a letter. For all y, if y writes a letter, then y is a police officer.
For all y, if y drinks water, then y is a police officer. There is at least one y for which if y were a police officer, then y is taking a plane.