Can you answer this extremely hard question? Imagine you are a doctor and you are trying to remove a tumor from a patient. You have a ray gun that you can use. If you put the ray gun on 100%, it will destroy the tumor, but it will damage the healthy tissue. If you put it on 10% or lower, it won't damage the tissue, but it won't destroy the tumor. How can you destroy the tumor without damaging the healthy tissue? Hint: You have an infinite amount of ray guns, but you need to use the minimum amount possible.