Read this: The German higher education system comprises two forms of academic institutions: universities and polytechnics (Fachhochschule). The University of Jena is the biggest amongst Thuringia's four universities and offers nearly every discipline. It was founded in 1558, and today has 21,000 students. The second-largest is the Technische Universität Ilmenau with 7,000 students, founded in 1894, which offers many technical disciplines such as engineering and mathematics. The University of Erfurt, founded in 1392, has 5,000 students today and an emphasis on humanities and teacher training. The Bauhaus University Weimar with 4,000 students is Thuringia's smallest university, specialising in creative subjects such as architecture and arts. It was founded in 1860 and came to prominence as Germany's leading art school during the inter-war period, the Bauhaus.

How many universities are missing in Thuringia?
What is the answer? (If it cannot be answered, return "unanswerable")
unanswerable