Answer:
i believe the answer is Greenbacks
Explanation:
Greenbacks was not used in the United States during its early years.
Greenbacks were paper currency, printed in green on the back, issued by the United States during the American Civil War.
Nowadays, Greenbacks is the slang used in the United States refering to paper money currently used.
In its early years, most people in United States only acknowledged metals including gold and silver as a legitimate medium of payments.
