What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? For all x_17, if x_17 works, then x_17 is a doctor. For all x_17, x_17 is a mechanic if and only if x_17 is a soldier. For all x_17, x_17 is a mechanic or x_17 will work. There is at least one x_17 for which x_17 is not a soldier.
For all x_17, if x_17 were a mechanic, then x_17 is a soldier. For all x_17, if x_17 were a soldier, then x_17 is a mechanic. There is at least one x_17 for which x_17 is not a mechanic.