Personal possession of currency is prohibited in u. s. prisons, although, in practice, prisoners still exchange goods and services. u. s. prisoners used cigarettes as a medium of exchange until smoking was banned in u. s. prisons in 2003. after 2003, prisoners looked to other items on the commissary menu to facilitate exchange. in 2008, the wall street journal reported that energy bars had caught on as money in some u. s. prisons. one important difference between using energy bars and using dollars as money is that have intrinsic value. u.s dollars are an example of money.

Here the energy bars have intrinsic value and U.S dollar are an example of fiat money.

Explanation:

According to this question, energy bars have intrinsic value which means it is an example of commodity money because commodity money is the one in which money takes form of a commodity which has intrinsic value ( that means it has its use other than money , for example eating ) .

U.s dollars are example of fiat money or fiat currency , where the it is a type of legal tender whose value is backed by the issuing government.

answer: yo mama

explanation: yo mama

answer; by looking at total product,marginal product,and changes in both after changes in inputs