1. If 800 units are sold at a price of $120 and 240 units are sold at a price of $180, what is the absolute value of the price elasticity of demand? Use the midpoint formula.
2. Which of the following pairs of items will have a negative cross-price elasticity, which will have a positive cross-price elasticity, and which will have zero cross-price elasticity?
a. Beef and pork
b. Air travel and weed killer
c. Shampoo and conditioner