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_7, x_7 will work if and only if x_7 will cook. There is at least one x_7 for which x_7 is an astronaut. For all x_7, if x_7 drives a car, then x_7 is cooking. For all x_7, x_7 will drive a car or x_7 will work.
For all x_7, if x_7 works, then x_7 is cooking can be inferred via the universal biconditional elimination rule. For all x_7, if x_7 cooks, then x_7 is working can be inferred via the universal biconditional elimination rule.