Problem 1 (15 points) For the following database, (a) list all the relationships among the records. (b) give some additional views that may be needed by other user groups. (c) give some examples of integrity constraints that you think should hold. Problem 2 (20 points) Which of the following plays an important role in representing information about the real world in a database? Explain briefly. (1) The data definition language. (2) The data manipulation language. (3) The buffer manager. (4) The data model