Washington's administration helped establish a strong federal government through the following actions:
D. by ratifying the Constitution - While the ratification itself was a process that involved the states, Washington's leadership and support for the Constitution were crucial in its acceptance and implementation, providing a framework for the federal government.
E. by enforcing taxes and laws - Washington’s administration took significant steps to enforce federal laws and the collection of taxes, such as during the Whiskey Rebellion, which established the federal government's authority to enforce its laws.
F. by establishing a national bank - The establishment of the First Bank of the United States under Washington's administration helped stabilize and improve the nation's financial system, enhancing the federal government's role in the economy.
Thus, the correct choices are D, E, and F.