Answer:
True
Step-by-step explanation:
Exchange rates vary through out different currencies ,controlled by different states .
The US dollar is the universal factor across all global currencies .Some may be higher while others may be lower but the USD is like the unit of comparison .
It is regulated by the federal reserve and is usually backed by credit .Money has taken dramatic twists , when it comes to backing as it has been backed by gold and oil before hence shifting from time to time .So the US discovered to gap which was filled by credit systems that oversee the flow of bills in relations to credit .