Final answer:
The institution of a presidential cabinet was begun by George Washington in 1789 when he appointed key positions such as Secretary of State and Secretary of the Treasury.
Step-by-step explanation:
The institution of a presidential cabinet was begun by George Washington. Although not explicitly mentioned in the Constitution, Washington established the first cabinet in 1789, appointing four key positions: Secretary of State, Secretary of the Treasury, Secretary of War, and Attorney General. These positions form the core of the presidential cabinet, which advises the President on various matters and helps with the administration of the government.
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