Trees convert light energy to chemical energy. when wood is burned, chemical energy becomes thermal energy. this heat can be used to run turbines (mechanical energy) that eventually create electrical energy. how would you model this transfer and conservation of energy?

By electric power station, where charcoal is used to produce electric energy.

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.