What are the three most important problems with the Articles of Confederation and why do they make a new Constitution necessary?

The three main problems with the Articles of Confederation would be that the states could impose trade barriers with one another, the Government couldn't collect taxes, and each state had their own currency.

Explanation:

When the states would impose barriers on one another this would promote products made in the state compared to other states. Ex. in Georgia a dress may be $15 but in New York the same dress made in Georgia would cost $30. This was also affected by each state having it's own currency, so say if you were in New York and your from South Carolina you would only be able to pay for the dress with the currency offered by New York. Not only this but the government couldn't repay France and Spain for helping in the war for the reason that no state was willing to give money and if they did the money would be rendered useless with every print made.

This would make a new constitution was needed for the reason that to be able to amend the articles you would need 9/13 states approval, which was hard to get and was eventually decided in the congressional congress that it would be easier to just write a new constitution.

We the people of The United States of America, deserve the right to live with natural rights and to be able to speak freely, have the freedom to have our own religion, and to be able to live in the pursuit of happiness.

using the scientific method.