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, if x_4 were a doctor, then x_4 is a poet. For all x_4, if x_4 takes a plane, then x_4 is a poet. For all x_4, x_4 is a doctor or x_4 will take a plane. There is at least one x_4 for which x_4 will make tea.
For all x_4, x_4 is a poet.