Federalism because Amendments are proposed at a federal level and is ratified at a state level. Why have only 27 Amendments been added to the Constitution? Because of Informal Amendments and how easy it is to informally amend it rather than formally.
<span>International trade enables specialization, which brings increased efficiency and greater competition to spur the market.
This happens becauseSpecialization would make each nation to focus on producing certain type of products in which they would gain a competitive advantage towards other (either because they had the necessary materials sources or labor qualities) and would create better and cheaper product in the market.</span>
It proves the solution in a real world setting that can be replicated and confirmed by others
