“por” would go in the blank because it’s referencing time
Hope this helps
Where’s the picture of the page
The University of Salamanca was established in the year <u>__1218__. </u>
2. A __<u>clase anual_</u>_ is a year-long course.
3. Salamanca is called __<u>La Ciudad Dorada__. </u>
4. Over 300,000 students attend the _<u>_La Universidad de Buenos Aires</u>__.
5. An __<u>examen parcial </u>__ occurs about halfway through a course.