Final answer:
The U.S. Constitution fixed the problems of the Articles of Confederation by strengthening the role of the federal government.
Step-by-step explanation:
The U.S. Constitution fixed the problems of the Articles of Confederation by strengthening the role of the federal government. Unlike the Articles, the Constitution created a stronger central government with expanded powers. This included the ability to levy taxes, regulate trade, and maintain a standing army. By granting these powers to the central government, the Constitution aimed to create a more effective and unified nation.