Equilibrium: Where Supply Meets Demand $-$ End of Chapter Problem

For each of the following situations, determine whether supply, demand, or both shifted and how.

In this instance, demand must have

b$.$ During winter, the number of daily air routes between Denver and Aspen, Colorado, increases, as does the price of a ticket.

In this instance, the must have

c$.$ From January through April in the United States, personal certified public accountants $($CPAs$)$ see a dramatic increase in their number of billable hours, but the average hourly rate of a CPA remains the same.

In this instance, must have