You have a stone weighing 40 pounds. You have to break it up into 4 parts such that using those weights in a scale and pan balance you can weigh anything from 1 pound to 40 pounds (integers only) Example: if you broke them as 5,5, 7 and 23, you can get 2 by putting 7 on one side and 2 on another. What are those 4 weights?