Why did so many investors begin to sell off their stocks, causing black thursday and leading to the beginning of the great depression?

The ancient greek city-state of sparta was run as an oligarchy , meaning

Which statement best evaluates the impact of the 1929 stock market crash on europe? 1. the united states established high export tariffs to europe that reduced goods exported to germany. 2. the united states promoted domestic policy initiates that reduced jobs on american bases in europe. 3. the united states promoted isolationism that withdrew troops from europe causing germany to pay its own national defense. 4. the united states eliminated loans to europe that caused germany to default on its reparation payments to france.

In what way did expansion and global trade during the 15th to 18th centuries affect the economies of european countries