What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? For all x_11, if x_11 were a mechanic, then x_11 is rich. For all x_11, x_11 is a nurse or x_11 is not rich. For all x_11, x_11 is not a cashier. For all x_11, x_11 is a cashier if and only if x_11 is a mechanic. For all x_11, if x_11 were a nurse, then x_11 is a mechanic.
For all x_11, if x_11 were a nurse, then x_11 is rich. For all x_11, if x_11 were rich, then x_11 is a nurse. For all x_11, if x_11 were a cashier, then x_11 is a mechanic. For all x_11, if x_11 were a mechanic, then x_11 is a cashier. For all x_11, x_11 is not a mechanic.