Which of these is an example of economies of scale? a. A ranch increases its profits by expanding from 400 to 800 cattle without buying or renting additional land.

b. A shoe store finds it can increase profits by hiring high school students who are willing to work for minimum wage.

c. An Internet access company charges customers different rates for using the Internet at different times of day.

d. A restaurant charges customers $1 a glass for water that was once provided for free.