Answer:
Solar ⇒ Tariffs
Tariffs are taxes on imported goods such that their prices are increased so that the domestic producers of that good can be able to compete with the imports which is the case here.
Numbers ⇒ Import Quotas
Import Quotas refer to limits on the amount of imports into a country. When the imports reach a certain amount they will be no more imports for the year.
Aluminium ⇒ Import Quotas
By only allowing a certain number of sheets to come into the country the US has imposed an import quota on the metal as per the definition above.
Materials ⇒ Embargoes and Sanctions
Embargoes and sanctions limit the trade of goods and services to the country under sanctions or being embargoed. Here the US will not ship goods to North Korea as they are under sanctions for their nuclear program.
Prohibition ⇒ Embargoes and Sanctions
This scenario describes an embargo which means that there is a ban on trade of certain goods and services with the nation under embargo.
Imports ⇒ Tariffs
Customs duties are taxes on imports which therefore makes them tariffs.
