Q.21 Answer the following questions You are invited as a database architect to develop database schema for maintaining data for a university database application Data requirements for a UNIVERSITY database: . The university keeps track of cach student's name, student number, social security number, current address and phone, permanent address and phone, birthdate, sex class (freshman, sophomore,.., graduate), major department, minor department if any), and degree program (B.A., B.S,. Ph.D.). Each student data also include the city, state, and zip code of the student's permanent address. Both social security number and student number have unique values for each student. Each department is described by a department name, department code, office number, office phone, and college name. Both name and code have unique valucs . Each course has a course name, description, course number, number of semester hours, level, and offering department. The value of course number is unique for each course. Each section has an instructor, semester, year, course, and section number. The section number distinguishes different sections of the same course that are taught during the same semester/year, its values are 1,2, 3up to the number of sections taught during each semester A grade report has a student, section, letter grade, and numeric grade (0, 1,2. 3,4 for F. D, C, B, A, respectively). . . . Note: you may need to have appropriate assumptions in requirements gathering process in order to make the specification complete. (a) Design the conceptual database schema using the ER diagram for this application. Specify key attributes of each entity type and structural constraints on each relationship type. a. (b) Map the conceptual schema to logical database schema (c) Show any referential integrity constraints among derived logical table schemas