A certain economy uses money that is made up of paper certificates. Each is called an Ounce Certificate because each one stands for exactly one ounce of gold held in storage. No Ounce Certificates are issued without an ounce of gold being stored for each. People in this economy can trade the Ounce Certificate for goods and services and be paid for work with the Ounce Certificate. They can also turn those paper Ounce Certificates in for gold at any time.
a. This economy uses ____
