course uniy fact table student dimension table area dimension table dimension table course id course_name department student id course id semester id instructor id count avg_grade student id student name area id major status university area id city province country semester dimension table semester_i id semester instructor dimension table year instructor id dept rank Using this schema, starting with the base cuboid (student, course, semester, instructor), what specific OLAP operations (e.g., roll up from semester to year) should one perform in order to list the following: to list the average grade for all of my students (my instructor_id is 007) to list the average grade for all CS majors to list the average grade for all CS majors in 2012 to list the average grade of English courses for each student to list the average grade of English courses for all students to list the average grade for each student in the year 2012 to list the average grade for all students in the year 2012 How many cuboids does this cube contain (including the base and apex cuboids)? (To make this caculation easier, you may ignore the area dimension of the snowflake.)