A local pizzeria hires college students to make pizza, wait on tables, take phone orders, and deliver pizzas. For each situation described, determine whether the demand for student employees by the restaurant would increase, decrease, or remain unchanged. Explain each answer.
a. The demand for pizza increases.
b. Another pizzeria opens up next door.
c. An increase in the minimum wage raises the cost of hiring student employees.
d. The restaurant buys a computer system for taking phone orders.