Energy is never destroyed it just turns into a form that is in useful as food

For instance, you take in chemical energy in the form of food, and do work on or destroyed, but it can change from more-useful forms into less-useful forms. ... it can never be turned into other (work-performing) types of energy with 100% ...

for many centuries there were important factors which the economies of the muslim empires developed increasingly. they applied economic procedures in production, investment, finance, taxation and property. they used to tax certain goods (for example: harvest), they charged interest on money lent, they signed contracts with merchants; they relied on a common currency, and they used checks as well as promissory notes. with the money collected by means of taxation, the government provided the needy with an income. in addition, trading networks covered huge distances, so far regions started to have contact and exchange goods. this trade network covered areas of asia, africa and europe.