1. (15 points) Identify the primary key and foreign key for the relations below. A database for DSU (Database State University) contains information about professors (identified by ProflD), Students (identified by StudentID) and courses (identified by Courseld). The database also stores students' grade info as well as professors' office infoThe database assumes that each professor has only one office, and up-to three professors can share a room (office). Professor (ProfID, FirstName, LastName, Building Name, OfficelD, Email) Student (StudentID, FirstName, LastName, Email) Course (CourselD, Course Title, Term, Year, Description) Grade (StudentID, CourseID, LetterGrade Office (OfficelD, OfficePhoneNumber, BuildingName, RoomNumber, Floor) Table -_-Primary Key Foreign Key Table Referenced Professor Course Student Grade Office