Stores are overflowing with the latest vampire novel $10.store managers are frustrated with the lack of sales . the equilibrium price for this novel is ?

The equilibrium price is less than 10 dollars.

Equilibrium in economic sense means that there is a balance,an equilibrium between the supply of goods and the demand for those same goods.  The demand and supply balance each other. If there is too much supply the price goes down and the demand will rise. That is the case here. If the bookstores reduced the price their demand would go up.