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: There is at least one x_12 for which x_12 will cook or x_12 will not sleep. For all x_12, x_12 is sad or x_12 will sleep. For all x_12, if x_12 were sad, then x_12 is cooking.
There is at least one x_12 for which if x_12 sleeps, then x_12 is cooking can be inferred via the existential rewriting rule.