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Technologies for Information Systems Part I (10 points) prof. L. Tanca – September 6th, 2016 Available time: 25 minutes Last Name _________________________________________________________________ First Name ________________________________________________________________ Student ID ________________ Signature_______________________________________ 1. Consider the following data mining problem: Sequential Pattern Discovery. Define and illustrate it clearly with an application example. 2. Define the concepts of valid time and transaction time in temporal databases also describing their advantages and disadvantages.  During this part of the exam, students are not allowed to consult books or notes.  Students should answer the theoretical questions using their own words, in order for the teachers to be able to assess their real level of understanding. Technologies for Information Systems Part II (22 points) prof. L. Tanca – September 6th, 2016 Available time: 2h 00m Last Name _________________________________________________________________ First Name ________________________________________________________________ Student ID ________________ Signature_______________________________________ Polimusic.com is a website allowing its customers to listen to songs by paying a fee for each listening. Each song has a specific price. 60% of the income derived by a listening is retained by Polimusic.com, whil e the remaining 40% is paid to the artists featuring the song. A song may feature more than one artist, and in this case the money is divided among the featuring artists on the basis of a weight. The management of Polimusic.com has now hired you to design a data warehouse to analyze the listenings. The following is the schema of the Polimusic.com operational database: ARTIST…