Which U.S. President, often referred to as 'Silent Cal,' pursued a policy of minimal government intervention and was known for his calm demeanor during a period of significant economic growth?

1. He assumed office following the death of a President.
2. His presidency was during the Roaring Twenties.
3. He famously stated, 'The chief business of the American people is business.'
4. He was known for his quiet and reserved personality, sometimes perceived as detached.