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, x_8 will work if and only if x_8 is a server. There is at least one x_8 for which if x_8 were a server, then x_8 is an office clerk. For all x_8, if x_8 cooks, then x_8 is working.
For all x_8, if x_8 works, then x_8 is a server can be inferred via the universal biconditional elimination rule. For all x_8, if x_8 were a server, then x_8 is working can be inferred via the universal biconditional elimination rule.