Physics homework help. Complete 14 page APA formatted essay: Chemistry in Life.to remember is that all forms of money are collectively called as currency, which in turn refers to all the money coins and banknotes which are generally accepted and in wide use in the country to which it pertains. The currency of a country is its so-called legal tender that in turn implies the medium of payment recognized by the countrys legal system. Implication in a country having a legal tender means it is valid for meeting a financial obligation. In other words, a creditor (lender) is obligated to accept any payment made in legal tender towards the repayment of a debt owed by a debtor (borrower). A good but short example is when someone pays in American dollars then the lender cannot refuse to accept such payment since a dollar is the legal tender in America (although some states accept gold or silver coins as payment). If the borrower intends to pay in kind (like mineral ores or cocaine or cattle or something else), a creditor can refuse such payment since it is not considered as legal tender and can be refused to be accepted to extinguish a debt, financial obligation or some other consideration.However, before coinage was invented, barter was used which is just a simple kind of exchange for one type of goods for another type of goods or resources. An example will be a person wants to buy a loaf of bread but lacking any money, he pays for it with a live chicken depending on their agreed value of exchange (there must be some semblance of parity). Most historians are generally agreed that coins were invented at around 700 B.C.E. (before current era) independently in Lydia (now a part of modern-day Turkey), in India, and in China. Barter is a form of direct exchange by which goods and services were exchanged for another set of goods and services without the benefit of using a medium of exchange (currency). Barter has a set of inherent problems such as the difficulty in determining the exact or accurate value of an intended exchange between two kinds of