Suppose an uncle left $500, and you had three choices for how to use the money. You could (1) save the $500 in a bank, (2) buy computer equipment, or (3) keep it in your closet. How would each of these actions affect the growth of the economy?

Traditionally the usual thing that was done was to put the money in a bank. If you live anywhere but the United States, that would not be a great idea. Even American Banks should be handled with care; you might just think about putting it in a bank. The effect would be that the bank would generate income for them and interest from them to you. The interest would be a very small part of what they take in, but it would be something. In the 1990's had an interest rate of over 20% which nothing to sneeze at. That no longer is a wise thing to do. I don't really think that banks are totally stable. So I wouldn't choose the first one.

You could buy computer equipment. I think I'd be tempted to do that. I would benefit because (if this is my first computer, I'd learn how to use it properly), and as mentioned before $500 is not a huge amount of money. I would benefit by learning a computer's virtues; the economy would benefit by creating how money gets around.

The most useless thing to do is put the money in a sock and put the sock in your closet. You don't get any benefit. The money becomes paper and you are getting nothing for it. So don't do this. It's pointless.