Question 1 You are given a use-case description about a possible solution for the Update Tariff process as shown in Figure 1 below: Use case name Update Tariff Participating actor Initiated by Central Computer System Flow of events 1. The Central Computer System activates the Update Tariff function of the ticket distributors available on the network. 2. The ticket distributor disables the traveller interface and posts a sign indicating that the ticket distributor is under maintenance. 3. The ticket distributor waits for the new database from the Central Computer System. 4. After waiting a minute for the ticket distributors to reach a waiting state, the Central Computer System broadcasts the new database. 5. The ticket distributor system receives the new database of tariff. Upon complete, the ticket distributor sends an acknowledgement to the Central Computer System. 6. After acknowledgment, the ticket distributor enables the traveller interface and can issue tickets at the new tariff. 7. The Central Computer System checks if all ticket distributors have acknowledged the new database. If not, the Central Computer System invokes the Check Non-Responding Distributors use case. Entry condition The ticket distributor is connected to a network reachable by the Central Computer System. Exit condition The ticket distributor can issue tickets under the new tariff, OR The ticket distributor is disabled and displays a sign denoting that it is under maintenance. Quality requirements The ticket distributor stays offline at most 2 minutes and is considered out-of-order otherwise. Figure 1 : A possible solution for the Update Tariff use case.

Based on the use-case description above, build a Use-Case Diagram.