RE: Lower and Upper Abbs Workout?
Having good abs is about low bodyfat %, not about how many swiss ball sit ups you do.
If you want a good 6 pack, sort out a healthy clean diet and go running for at least 30mins everyday. Running isn't even necessary if you have your diet to a T.
If you feel the need to do some weights to aid your 6 pack, weighted crunches once a week are all you need.