Final answer:
The percentage of lymph draining to the internal mammary chain can vary depending on various factors. It can range from 10% to 40% of the total lymph flow from areas like the breast, chest wall, lungs, and diaphragm.
Step-by-step explanation:
The percentage of lymph draining to the internal mammary chain can vary depending on various factors. The internal mammary chain is a group of lymph nodes located close to the sternum or breastbone. It receives lymph drainage from various regions like the breast, chest wall, and some portions of the lungs and diaphragm. This drainage can range from 10% to 40% of the total lymph flow from these areas.