What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? For all x_7, x_7 is a nurse or x_7 is an artist. There is at least one x_7 for which x_7 is a scientist or x_7 is not an artist. For all x_7, x_7 is a nurse if and only if x_7 is a scientist.
There is at least one x_7 for which if x_7 were an artist, then x_7 is a scientist. For all x_7, if x_7 were a nurse, then x_7 is a scientist. For all x_7, if x_7 were a scientist, then x_7 is a nurse.