Explain why it is usually more difficult to study and control efficiency in a social system than in a physical system?

In a social system, there are peers and strangers to distract one from pursuing their work. While chatting with others, you may forget your train of thought or a good idea. People are likely to take you away from your work more so than a physical system (in which you can always turn off the TV, but not get people to quiet down)

Sorry sir you did not give us the graph i typically but i'm very confused my conclusion is you're missing valuable information in the question

Yes, some people used the depression to the max. not everybody had stocks, and those that didn't bought many things inexpensive, so that when prices rose again, they were much more richer than beforehope this