Start with a 72 hour fast and see how you feel. (On snake water) I would estimate, if you have not been restricting already, you will lose 5 to 8 pounds from food still digesting and some water. And 16 or more by doing roiling 48s or 72s with not refeeding to heavy
This guy lose 60lbs in 4 weeks.
Probably possible. I heard that a normal rate is around 1/2 pound per day, so you need to push yourself quite a bit to more than double that rate. It will be hard and uncomfortable.
walk, run, stand all day
swimming in water not too hot will use a lot of energy.
expose yourself to cold, wear shorts/t-shirt at home, keep the temperature low, sleep with fewer blankets.
you can also take cold showers to push it farther.
​
Even if you lose *only* 20 ponds, you will feel amazing at the end of the month!