Answer:
It's because they provide communication and data security
The Decisions at the Atlantic and Yalta conferences affected the structure and purpose of the United Nations because they showed that to keep peace in countries, these countries must be stable. It also called for freedom of elections and the right of people to choose their own leaders in Soviet Union territory, although the Soviet Union greatly opposed this.
Basically, the conferences made sure there would not be another horrific world war
The event of the stock market crash put the entire nation into "The Great Depression", which made the economy plummet. Trade world-wide was effected, and people were scared to put, and trust their money to be kept in banks. So as an alternative, they'd stuff their cash in their homes, wherever they could hide it.
