The relationship between the price of music CDs and the quantity supplied and demanded is given below: Price Quantity Demanded Quantity Supplied $9 40 million $10 60 million $11 80 million $12 $13 100 million 90 million 80 million 70 million 60 million 100 million. 120 million If the industry price is $12, there is a 4 equal to million CDs.