Answer:
- Currency based System
- Wheels / Caravan
- Ink / paper
Step-by-step explanation:
The slik road connected 3 continents: Asia, Europe, ad Africa.
Wheels / Caravan was important the main method of goods distribution via Land.
Before currency was invented, people conducted their trades through barter. This means that if you want to obtain a certain good, you need to exchange it with another good.
This was a massive problem in international trade since not all countries give the same valuation toward the same product. This is why trading system based on currencies were an important invention for the silk trade. They measure a certain type of good with coins or golds so all nations can have the same form of measurement.
Beside coins / gold, many traders use contracts as a proof of purchase. This could only be done because of the invention of ink/paper that popularize by the Chinese government.