a. As the Chewy sandwich chain expanded, it received volume discounts on meats, produce, paper products, and other items.
b. As the Polaris marketing firm expanded overseas, the difficulty of managing the enterprise across several languages and time zones led to higher average costs.
c. Costs at Patel Accounting LLC are steady regardless of how many clients the firm has.
d. Northside Rehabilitation was able to cut costs while expanding by having its staff specialize in different treatment methods.