3 The following chart presents data on the price of fuel oil, the amount of it demanded, and the demand for insulation.

(a) Calculate the price elasticity of demand for fuel oil as its price rises from 30 cents to 50 cents; from 50 cents to 70 cents.

(b) Are fuel oil and insulation substitutes or complements? How can you tell from the figures alone?

Fuel Oil Insulation Price per Gallon Quantity Demanded Quantity Demanded

(Cents) (Millions of Gallons) (Millions of Tons)

30 100 30 50 90 35 70 60 40