To open a new business, a manager must obtain a license from the city for $20,000. The license is transferable, but only $3,000 is refundable in the event the firm does not use the license. a. What are the firm's fixed costs? Sunk costs? b. Suppose the manager obtains a license but then decides against opening the business. If another firm offers the manager $2,000 for the license, should the manager accept the offer?