Final answer:
To break an anchor free from the bottom, you can use a pulley system and attach a buoy or marker buoy to the anchor chain closer to the surface. By applying tension on the buoy, the anchor can be freed from the bottom with less force.
Step-by-step explanation:
When retrieving an anchor from the bottom, you can break it free by using a pulley system. One method is to attach a buoy or marker buoy to the anchor chain closer to the surface. Then, you can use a boat or another vessel to apply tension on the buoy, causing the anchor to break free from the bottom. This method helps to reduce the force required to break the anchor free.