Final answer:
Non-self supporting ladders must be set up at a ratio of 1:4, meaning for every four units of height, the base should be one unit from the wall. The question segments provided, however, deal with calculating forces on a ladder in static equilibrium rather than ladder setup ratios.
Step-by-step explanation:
Non-self supporting ladders must be set up at a specific ratio of the ladder's length to the distance from the wall to ensure safety and stability. This setup is described using an angle, but it can be translated into a ratio of 1:4, meaning that for every four units of height, the base of the ladder should be one unit away from the wall. However, the information provided in the question segments does not specify this ratio directly but involves more complex static equilibrium problems to determine forces acting on a ladder.