What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? Name the inference rule being used: For all x_8, if x_8 works, then x_8 is a scientist. For all x_8, x_8 is a scientist if and only if x_8 is an office clerk. For all x_8, x_8 will work or x_8 is an office clerk. For all x_8, x_8 will take a plane.
For all x_8, if x_8 were a scientist, then x_8 is an office clerk can be inferred via the universal biconditional elimination rule. For all x_8, if x_8 were an office clerk, then x_8 is a scientist can be inferred via the universal biconditional elimination rule.