GGG Company has entered into a contract with its financial institution that would allow it to issue its own digital cash. GGG would create sequenced notes that would be digitally signed with one of several private keys. The exact keys used would depend on the denominations of the individual notes.

GGG would then electronically transmit the signed notes to its suppliers, who in turn would either use them somewhere else as cash or present them to GGG's bank for collection.

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How well would GGG's payment system work? What problems might arise?