2. The cross-price elasticity is a. positive for normal goods. b. negative for substitute goods. c. negative for complementary goods. d. positive for inferior goods. 3. The income elasticity of demand is a. positive for normal goods. b. negative for substitute goods. c. negative for complementary goods. d. positive for inferior goods. 4. The interval method is used to compute price elasticity a. when a price change causes a relatively large movement along demand. b. so elasticity can be computed for rather small changes in price. c. for nonlinear demand curves because point elasticity cannot be computed for curves. d. because demand curves are downward sloping