Which of these describes an item for which a change in its supply is proportional to a change in its price ?

Unit Elastic

A unit elastic demand describes an item that assumes a change in its supply will cause an equal proportional change in its price or quantity demanded. For example; if a person raises the price of her product like apple pie by $1.00, the unit elastic demand for that one dollar increase would mean a decrease in the quantity demanded by one unit. Therefore, unit elastic demand defines an item that describes a demand or supply that is perfectly responsive to price changes by the same percentage.

their visual appeal is a sure hook into their content. but big books are also produced for pedagogical reasons, and using them in the classroom makes good teaching sense. an abundance of good children's literature in their lives is vitally important for young children as they strive toward independent reading.