What did Jerome Powell do before he was chairman ?

He moved to investment banking in 1984, and worked for several financial institutions, including as a partner of The Carlyle Group

Explanation:

Powell served as an assistant secretary and as undersecretary of the Treasury under President George H.W. Bush. There, he was responsible for policy on financial institutions, the Treasury debt market, and related areas. Before joining the administration, he worked as a lawyer and investment banker in New York City.

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congress also has implied powers, which derive from the necessary and proper clause of the constitution and permit congress "to make all laws which shall be necessary and proper for carrying into execution the foregoing powers, and all other powers vested by this constitution in the government of the united states.