2. What are the most important things you have learned in this unit about how the trillions of cells in the human body get what they need to function, and what they do with the things they absorb?

answer: 20 percent

the fish culture has become a developing commercial practice in developing countries which is already prominent in developed countries of the world. the major fish protein demand is being supplemented in developing countries is   fishing to meet the needs of the growing population. therefore, in some developing nations, the percentage of animal protein from fish in the diet can be as high as 20 percent.

b is the answer and if you need further with anything message me