What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? For all x_4, x_4 is poor if and only if x_4 is a scientist. For all x_4, x_4 is a scientist or x_4 is a nurse. For all x_4, if x_4 were a nurse, then x_4 is poor.
For all x_4, if x_4 were poor, then x_4 is a scientist. For all x_4, if x_4 were a scientist, then x_4 is poor.