The headline on a personal technology column in the Wall Street Journal in late 2022 was “These Next Generation Headphones Don’t Even Go in Your Ears.” According to the column, unlike the earbuds that many people use with their smartphones, “bone-conduction headphones are built differently. . . . They rest above your ears, leaving your ear canal unencumbered, and vibrate against the part of your skull adjacent to your inner ear.”

a. Are bone-conduction headphones substitutes for or complements to smartphones? Briefly explain.

b. Suppose that the price of smartphones increases. Use a demand and supply graph of the market for bone-conduction headphones to show the effect on the equilibrium price and quantity. Be sure that your graph shows the equilibrium price and quantity before and after the increase in the price of smartphones.