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, if x_7 cooks, then x_7 is running. For all x_7, if x_7 goes running, then x_7 is cooking. There is at least one x_7 for which if x_7 cooks, then x_7 is running.
For all x_7, x_7 will cook if and only if x_7 will go running can be inferred via the universal biconditional introduction rule. For all x_7, x_7 will go running if and only if x_7 will cook can be inferred via the universal biconditional introduction rule. There is at least one x_7 for which x_7 will cook if and only if x_7 will go running can be inferred via the existential biconditional introduction rule. There is at least one x_7 for which x_7 will go running if and only if x_7 will cook can be inferred via the existential biconditional introduction rule.