Let's see what happens when the price of a product          
causes the demand to decrease.

A shopkeeper has received a shipment of one thousand little plastic "Zuzuloopers," what he hopes will become a new craze for the local children.  Since Zuzuloopers are not yet popular, or in demand, he sells them cheaply.  Before the week is out he has sold 1,000 of them for $1.00 each.   The supply is gone, but the demand is now high.
When a new shipment of Zuzuloopers arrives, the shopkeeper decides to make a larger profit and raises the price to $3.00 apiece.  Since sales are still strong, at the end of the week, after selling 500, he raises the price again to $5.00.
He notices that fewer children are coming to his shop, but there is still a demand for Zuzuloopers.  "If the children really want them, they will pay!" he thinks to himself as he raises the price to $10.00.  Sales are now slow, but the shopkeeper is making a much larger profit.  "Just think, I am selling these little things for $10.00, and even though most children can no longer afford them, I did sell fifty Zuzuloopers in the past few months.  That's $500!  I am a great businessman!"
"Once more, I will raise the price.  Just think, if there are children who will pay $10.00, there must be some who can pay $20.00!"
With 250 Zuzuloopers in the storeroom, the shopkeeper sits and waits...
       and waits...
                   and waits...
                                  Can you help him figure out what to do?

Look at the graph of Zuzulooper sales, then  answer the questions below.