This is an example of how a quota promotes trade.
- China is the place with productivity since it's like the "power source" most places trade with it whereas Australia uses the produce and turns it into the new gen. technology.
- A tariff is when a certain tax has to be paid from importing things.
- Specialization is for places that make use of native things, they specialize on certain things for instance some places are know for their tech., some for farming and irrigation.
- A quota is when there is a fixed share amongst the traders. Like in the paragraph it mentioned how china gives to australia and australia gives a balance back.
Hope this heps and have a great day!