UTD is making classroom building expansion plans for the next 10 years. It is going to forecast the student enrollments. What is the appropriate time bucket and student aggregation level. 1. Time buckets: semesters. Aggregation level: Online students, In-class students. 2. Time buckets: semesters. Aggregation level: Generic UTD student. 3. Time buckets: months. Aggregation level: Generic UTD student. 4. Time buckets: months. Aggregation level: Management students, Engineering students, and Arts&Sciences students