Problem: In about 260 AD, the fall of the Agri Decumates territory north of the Rhine transformed today's Switzerland into a frontier land of the Empire. Repeated raids by the Alamanni tribes provoked the ruin of the Roman towns and economy, forcing the population to find shelter near Roman fortresses, like the Castrum Rauracense near Augusta Raurica. The Empire built another line of defense at the north border (the so-called Donau-Iller-Rhine-Limes), but at the end of the fourth century the increased Germanic pressure forced the Romans to abandon the linear defence concept, and the Swiss plateau was finally open to the settlement of German tribes.
What was the name of the concept used by the Roman Empire when building another line of defense at the north border?
The answer is the following: the linear defence concept

Problem: The Pashupatinath Temple is a famous 5th century Hindu temple dedicated to Lord Shiva (Pashupati). Located on the banks of the Bagmati River in the eastern part of Kathmandu, Pashupatinath Temple is the oldest Hindu temple in Kathmandu. It served as the seat of national deity, Lord Pashupatinath, until Nepal was secularized. However, a significant part of the temple was destroyed by Mughal invaders in the 14th century and little or nothing remains of the original 5th-century temple exterior. The temple as it stands today was built in the 19th century, although the image of the bull and the black four-headed image of Pashupati are at least 300 years old. The temple is a UNESCO World Heritage Site. Shivaratri, or the night of Lord Shiva, is the most important festival that takes place here, attracting thousands of devotees and sadhus.[citation needed]
When was the Pashupatinath Temple built?
The answer is the following: 5th century

Problem: Bilateral treaties are concluded between two states or entities. It is possible, however, for a bilateral treaty to have more than two parties; consider for instance the bilateral treaties between Switzerland and the European Union (EU) following the Swiss rejection of the European Economic Area agreement. Each of these treaties has seventeen parties. These however are still bilateral, not multilateral, treaties. The parties are divided into two groups, the Swiss ("on the one part") and the EU and its member states ("on the other part"). The treaty establishes rights and obligations between the Swiss and the EU and the member states severally—it does not establish any rights and obligations amongst the EU and its member states.[citation needed]
Bilateral treaties are concluded between how many states or entities?
The answer is the following: two

Problem: Czech has one of the most phonemic orthographies of all European languages. Its thirty-one graphemes represent thirty sounds (in most dialects, i and y have the same sound), and it contains only one digraph: ch, which follows h in the alphabet. As a result, some of its characters have been used by phonologists to denote corresponding sounds in other languages. The characters q, w and x appear only in foreign words. The háček (ˇ) is used with certain letters to form new characters: š, ž, and č, as well as ň, ě, ř, ť, and ď (the latter five uncommon outside Czech). The last two letters are sometimes written with a comma above (ʼ, an abbreviated háček) because of their height. The character ó exists only in loanwords and onomatopoeia.
What character in Czech only exists in loanwords?
The answer is the following:
ó