What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? Mary is a cashier. For all x_5, x_5 is a politician if and only if x_5 is a cashier.
There is at least one x for which x is a cashier. For all x_5, if x_5 were a politician, then x_5 is a cashier. For all x_5, if x_5 were a cashier, then x_5 is a politician.