Answer: The Romans used gold, silver, and bronze coins for trade and to pay taxes. Goods came to the Roman Republic from several regions outside of Italy.
Explanation:
Archaeological and written sources prove that the Romans used money in exchange. The Romans had a highly developed monetary system, one of the highest quality in all of antiquity. It was common knowledge that the Romans had a highly developed trade, so they traded with many countries outside their state's borders. Luxury goods from other parts of the world came to Rome most often.
There are three main reasons for European Exploration. Them being for the sake of their economy, religion and glory. They wanted to improve their economy for instance by acquiring more spices, gold, and better and faster trading routes. Also, they really believed in the need to spread their religion, Christianity.
Revenue means "money coming in" or "income"
The answer for your question is the 3rd answer